accsyn user manual

Rev 1.014, 20.11.19

Welcome to the accsyn user manual, here we will guide you through the desktop application and web interface - how to get started transferring files and monitoring/controlling ongoing transfers.

Additional resources:

- The manual for setting up accsyn on your premises can found here: Admin Manual

- The manager guide describing how to send and receive files can be found here: Manager Guide

What is accsyn?

accsyn stands for ACCelerated SYNchronised file transfers and is a software for secure, fast and reliable delivery of large file packages with metadata to and from an organization - a replacement for WWW file transfers or dated/insecure file services like FTP. From now on we will identify an organization by its "domain", which in turn defines the address to the accsyn web page: https://<domain> We describe further below how to upload/download and monitor transfers using your web browser.

Where can I run accsyn?

Besides having access to the Internet you need to be able to run a supported operating system and a supported browser:

Desktop app/server:

  • Windows (7+)

  • Mac OS X (10.7+)

  • Linux/unix,

In general any system where Java JRE 1.7 can run. (contact us if you need to run in JRE 1.6 or lower)

Web browser interface

  • Chrome (recommended)

  • Firefox

  • Edge

  • Opera

  • Safari

  • Internet Explorer 9+

Where do I download accsyn?

It all starts with an invitation E-mail sent to you, the invitation E-mail contains instructions on how to activate your account if you are a first time user. If you have used accsyn with another domain, you already have set a password and do not need to activate account.

You can also join an accsyn domain by yourself by opening the domain in your web browser (<domain> and choose Join. If Auto join feature is turned on for domain, you will get an activation E-mail and can proceed download and use application. Otherwise, a join request will be sent to domain admins, when approved you will receive the activation E-mail.

How do I activate my account?

  1. Click the green link button in E-mail.

  2. It will open in your web browser.

  3. You will have to choose a strong password: containing at least one lowercase letter + on uppercase letter + one digit, having at least 8 characters.

Downloading and installing accsyn app

Once you have activated you can download desktop app by:

  • Following the link provided in activation/join E-mail.

  • Download from, follow Download link.

  • Logon to accsyn using your web browser and follow the GET APP link in upper right corner:

  • Use direct download links:




Installing accsyn

Run the downloaded installer, it will first install the software and then launch directly after.

Install troubleshooting


    • Java comes bundled with the Windows installer, there is no need to install Java in advance.

    • Windows defender might block installer telling you application is unrecognised, solve this by clicking the Run Anyway button or More info > Run Anyway.


    • The .dmg will appear as a mounted disk image. Run the installer within.

    • Java comes bundled with the Mac installer, there is no need to install Java in advance.

    • A dialog appears telling you that developer cannot be verified; fix this locating the downloaded DMG in Finder > Right click > Click "Open".

    • (Catalina+) In some cases, GateKeeper within Mac OS X might still reject accsyn. Attempt setting the extended attribute on launchers: sudo xattr -r -d /Applications/Accsyn.


    • Sometimes double-clicking on the downloaded file does not launch the installer, in that case open a terminal and run it manually: sudo ./

    • The installer relies on Java being present at the host. RHEL/CentOS 7 and earlier; sudo yum install java-1.8.0-openjdk-headless . RHEL/CentOS 8: sudo dnf install java-1.8.0-openjdk. Ubuntu: sudo apt-get install -y default-jdk.

    • The permissions of the installer need to grant execution rights, run chmod 755 to fix permissions and then retry installer launch.

The installer runs without any user inputs required (unattended mode) by default, installing into default operation system application install location. To run installer in GUI mode and choose installation destination, run the installer from a terminal/shell/DOS window with the "-g" parameter supplied.

I have a personal firewall and/or antivirus software

Besides allowing the installer to install the software (elevated/admin/root access needed), accsyn requires the following:

  1. Be able to reach the Internet at port 443 (tcp, https REST), specifically "" and "<domain>" where domain identifies the organization you are to connect to.

  2. Be able to reach the Internet at ports 45190-45209 (tcp, accsyn fast copy protocol), specifically the remote server that you will communicate files with.

Consult your firewall-/antivirus software manuals for instructions on how to add exceptions for accsyn to allow the traffic above.

Note: different ports than 45190-45220 can be configured for a domain, if you have connection problems with your transfers - make contact and find out which ports you need to whitelist in case you are in an restricted network environment.

accsyn client (desktop app & daemon) supports standard SOCKS (v4/v5), configured in app or supplied as environment variables.

Configure in app

At login screen, click "Proxy settings" link to open up dialog were you can enter the hostname and address of your proxy server and port. The link will have a green check mark when proxy is configured.

Configure using environment variables

Set the following environment for accsyn to pick up at launch:

ACCSYN_PROXY=socks:<hostname or IP>:<port,defaults to 1080 if not supplied>

Logging on to accsyn

You will be presented the login dialog when you launch accsyn:

  1. Enter your E-mail address , the one that got the invite, and hit NEXT.

  2. Enter the your password and hit LOGIN.

If you have problems logging in, check the following:

  • Make sure you typed your E-mail address right.

  • Enter password exactly as it is, with correct case, as accsyn is case sensitive.

  • If you have forgot your password, hit Forgot password?. It will take open the password reset mechanism in your browser, follow the instructions on how to recover your password.

The accsyn main window

  1. File browser/create new file transfer area.

  2. Monitor file transfers area.

  3. Enable/disable accsyn; Disable accsyn on this computer - stop transfers. Enable to have them proceed.

  4. Preferences; open user prefs.

  5. My transfer; Show ongoing/active transfers.

  6. Finished; Show finished jobs, search the archive.

  7. Minimise/maximise view buttons. Use these buttons to expand a view to fullscreen, minimising the other.

Receiving packages

When you have an incoming file package, you will first receive an E-mail notifying you. Check your mailbox, if not found - try looking among your spam filtered E-mails as it might have been treated as spam.

If the package is less than 2GB you can choose to download it using your web browser, simply follow the link provided in E-mail. If you have the desktop app at hand, it is recommended to download using it instead as it will go much faster. Open and login to accsyn, it should prompt you that a new package is ready for download:

Choose YES and browse to were files should be saved. You can anytime follow the progress and get an ETR of delivery through the desktop app or by using your web browser.


Keep accsyn app running until transfer has finished, if you close the app too early the package might not have finished and you will have to launch app again to get it through.

The share concept of accsyn

Before we send away our first file package, lets get familiar with the term "share" used in accsyn.

A share is a folder on the remote organization given access to user for download (and upload), compare it to an FTP account or Dropbox folder.

You mostly have access to at least one share and that is called your Home share. This is your personal folder for storing files, accessible only by you and the organization/domain.

Note: you might not have been assigned an home share, don't worry - you will still be able to receive packages sent to you. If you need to upload and do not have access to any share(s) - contact your accsyn domain representatives and have it sorted.

Sending files

We are now ready to send files away, there are two ways of initiate a file send:

  1. Select and drag-n-drop files from your file browser (i.e. Explorer/Finder) onto accsyn, or

  2. Show the "New transfer area" and, on the left hand side, choose the file(s) to upload and click [ UPLOAD ] button in the lower right corner.

If you have a home share, accsyn will suggest to "dropoff" the file(s) and will give you the option to autostart the transfer. Dropoff means files will be uploaded to your home share, typically in a date folder named YYYYMMDD.

Hit Submit or leave it to time and package will be submitted. Choose No, I want to review and you will be able to alter the file package (see below).

Download files

To download one or more files, expand the New transfer view:

The submit dialog consists of the following inputs:

  1. Source/from selection.

  2. Destination/to selection.

  3. File browser area; displays locations (shares or local drives) and files/directories, with size and modification timestamps.

  4. Destination mode; mirror paths - transfer preserving directory structure, browse - manually choose destination directory and dropoff - automatically pick a suitable destination location.

  5. Address bar; shows where you are at.

  6. Toolbar button; perform various file operations: go up one step, go back, goto a path (history), create directory, rename file, move file and delete file.

  7. A share, in this case a home share.. Right click to bring up options.

  8. File listing; sortable by clicking the column headers. Right click to bring up options.

  9. File import; select files from a list, one entry per line that can be copy-and-pasted from somewhere else.

  10. Build a large file package with files from different locations/directories.

  11. Enter a custom name for file transfer package, leave empty a it will be named as first entry filename.

  12. Transfer settings, set bandwidth limit and other parameters.

  13. Submit the file transfer to accsyn - start copying files. A confirmation Email will be sent when file transfer is completed.

File operations you can do on remote workarea are:

  • Create directory; Create a directory where you currently stand, not below any selected folder.

  • Rename the file or directory you have selected in file browser.

  • Move the file or directory you have selected, a new dialog will appear for you to select the destination for file.

  • Delete file or folder; remove file or directory at remote work area after confirmation. If directory contains one or more files a second warning and confirmation will be shown.

Building file packages

The file package list shows source and destination paths, with a summary above showing file size (if local file) and number of files.

Remove files/directories from the package by selecting them and hit Remove selected button, or hit the trashcan symbol at the end of each entry.

Working with your active transfers

How does accsyn transfer files?

accsyn transfer files, between desktop app and server, adhering the UNIX "rsync" protocol - copying files that have a change in modify date or size. Some rules and limitations:

  • Resume on single files is not supported, an interrupted transfer will only resume from previously completed set of files.

  • accsyn utilises the Internet as efficiently as possible by issuing multiple TCP large buffer transfer channels and file readers, somewhat comparable to FTP upload using multiple connections.

  • Aborting a job does not remove any transferred files, they have to be removed manually.

Job list

The accsyn main window lists the active transfers sorted by the order they will be executed.:

  • Expand button [+]; Display files in package.

  • Download(green - down)/upload(blue - up) icon.

  • Status, speed and ETR; The job status: no icon=waiting, play icon = in progress, two yellow vertical bards = paused/on hold, red cross icon = aborted, green checkmark = transfer successfully done. The current transfer speed is displayed in Megabyte per second (MB/s).

  • Name; The name of transfer job, with progress bar and progress printed at right hand side.

  • Source > destination.

  • Size; The size of package.

  • Eta; The estimated time remaining.

  • Created & Time; The time job were created & the age of job, since it was submitted.

Modifying job

Right click job to bring up job context menu.

  • View; Open job detailed view.

  • Browse; Open Finder/Explorer at directory.

  • Pause; Pause the job - will immediately interrupt the job.

  • Resume; Resume a paused or failed.

  • Rewind; Rewind job to start.

  • Abort; Abort a transfer.

Job view

The job view displays detailed information about the job - listing the files in package and their status. From here you can also edit the job - set bandwidth limit. To open up the job view, right-click the job and choose view.

Prioritising jobs

Sometimes you need to have one transfer go ahead of another, in that case:

  1. Pause the lesser important transfer(s), leave the important running.

  2. Resume the lesser important transfer(s) again, they will start as soon as the important transfer is done (or paused/failed/aborted).

Working with files

For packages containing multiple files/tasks, each task can be modified independently. This include:

  • Setting on or more files to done.

  • Retry one or more files.

  • (Non restricted users) View the transfer log, troubleshoot transmission.

  • Change the priority of files - have high priority files being sent before low priority.

Troubleshooting jobs

Sometimes the job does not start or simply fails, this can be due:

  • Job is being initialised or is paused.

  • Job is not dispatchable yet - is below another job in queue. Recall that accsyn uses job queue over at domain, although you cannot see the overall queue status job might still be below another job in queue and is waiting to be started.

  • a resource being offline, for example your desktop app/server/share/site or other disabled needed resource.

  • Job is already finished, have a look in the Finished job list.

  • The disk you are downloading to has disappeared (unmounted) or have not enough space.

  • The server has lost connection to its volume at domain or has run out of space.

  • A network connection could not be established, mostly due to blocked TCP ports either at sender or receiving end.

  • The network are having stability issues, you might be on mobile connection that is partially offline or the remote server are facing connection issues.

To get some more information, first view the job and open the log:

The log might give you some hints on what has gone wrong and how to remedy it. If you still cannot get your job going, have a look at our troubleshooting guide and then contact domain representatives before you attempt to contact accsyn support team.

IMPORTANT NOTE: The accsyn support team only answers on technical issues relating to the software, we are not responsible for job queues or resources at a specific domain that most probably is the cause of failure.

Configuring your accsyn

The preference section can be reached by clicking the Email + gearwheel icon in upper right corner. Here you can find helpful links to resources and make configurations.


Click the button to open your profile in your web browser - change name and other contact information, also get your API KEY for automised CLI/Python API operations.

Shares - map a share to a local path

This is useful when you are receiving a lot of material from a share and you want them to be autosaved in a specific location locally. Select the share and browse to where files should be stored.

Tick the additional Read and Write checkboxes if you want to allow domain employees/admins (not other restricted users) to browse and download/upload from/to your locally mapped share.

You can also make this mapping by defining an environment variable, giving an example: if share "xyz" is to be mapped onto "D:\xyz", set the environment variable "ACCSYN_XYZ_PATH=D:\xyz" and then restart accsyn to have it apply. (Setting it as a system wide environment variable allows eventual background accsyn daemon/service to see it).


If your issue cannot be resolved by studying the job log, or other transfer related issues, try to find a solution at our Troubleshoot support section.

If you still are stuck, send the log files to and describe step by step what triggers the issue, more information on support main page.

Client log file location

  • Windows: "%appdata%\accsyn\log". %appdata% usually points to the AppData\Roaming folder beneath your system account.

  • Mac OS X: "~/Library/Logs/accsyn". "~" means your system account directory.

  • Linux: "~/.accsyn/log". "~" means your system account directory.

Local preference storage

The accsyn app stores its preferences, like last used login and UI settings, beneath the local account on disk:

  • Windows: "%appdata%\accsyn". %appdata% usually points to the AppData\Roaming folder beneath your system account.

  • Mac OS X: "~/Library/Preferences/com.accsyn". "~" means your system account directory.

  • Linux: "~/.accsyn. "~" means your system account directory.

Remove these folders while the application is not running, to start a clear session.

Web interface

accsyn has a web interface/application that can be reached from both a desktop computer and a mobile phone/tablet.


To reach the web interface, follow the link supplied in your invitation E-mail or go to: https://<domain>, logon using your E-mail and password as you would use to access the desktop app.


The web interface is self-explanatory and contains plenty of hints on how to perform the tasks.

Users can perform the following basic duties:

  • Download the desktop app.

  • Recover lost password.

  • Change your current password/regenerate API KEY.

  • Request to join accsyn (if enabled by domain admins).

  • Download a smaller package (<2GB).

  • Upload a smaller package (no file larger than 2GB)

  • Monitor your ongoing transfers using the mobile friendly web interface.

Employees can:

  • View all transfers.

  • Send packages to users.

  • Invite users.

Python API

For information about the accsyn Python API, please visit: accsyn Python API Documentation

Running a background service/daemon (server)

Running Accsyn as a background service allows file transfers to happen without needing to start the desktop application, or even logon to your machine. This is highly suitable for setups where availability is crucial, it becomes extra useful if you configure local share paths - makes it possible for accsyn to send files to you 24/7 as long as computer is running.

Getting the installer

  • Logon to accsyn using your web browser (<domain> and follow the GET APP link in upper right corner.

  • Tick "Show server downloads" to reveal the download links, choose the installer for your platform and download.


  • Start installation, instead of authenticating using PIN, choose login.

  • Login using your credentials and then finish installation.

From now on, all transfers will go through the server if it is online. If it gets turned off, transfer packages will go through the desktop app as usual until it goes online again.

NOTE: Jobs that once has bound to a client will not move, for example a heavy download that goes through the desktop app cannot be "moved" to the background server if already spawned (chosen a destination).

Additional resources

Frequently ask questions, changelog and tutorials can all be reached at:

Here you will get access to the knowledge base containing answers to common questions you might have.

Contacting support

If you have technical issues using the desktop app or the web interface, and you cannot find a solution to your problem @, feel free to send a support ticket by E-mail to:

Always be careful to state your issue properly in the E-mail subject so we can answer more efficiently.

Good luck with your smooth file transfers!


/The accsyn team