Category: Installation, Version 5.x

SimpleSYN supports the following versions of Microsoft® Windows® and Outlook® 

  • Microsoft® Windows®
    • Windows® 10 Anniversary Update or newer (32-bit/64-bit)
    • Windows® 8.1 (32-bit/64-bit)
    • Windows® 7 SP1 (32-bit/64-bit)
  • Microsoft® Windows® Server
    • Windows® Server 2016
    • Windows® Server 2012
  • Microsoft® Outlook®
    • Office 365® with Outlook®
    • Outlook® 2019 (32-bit/64-bit)
    • Outlook® 2016 (32-bit/64-bit)
    • Outlook® 2013 (32-bit/64-bit)
    • Outlook® 2010 (32-bit/64-bit)

For the program to run smoothly there are the following requirements

  • A active Internet connection is required during the synchronization (SimpleSYN Business and SimpleSYN Standard) and the PCs must be turned on at the same time (no cloud service is used)

Please note:

  • The Windows service is only available in the SimpleSYN business version. In the SimpleSYN standard version, a Windows user must be logged in to the computer for synchronization
  • You cannot synchronize your Google calendar or iCloud data with SimpleSYN

Category: Installation, Version 4.x, Version 5.x

SimpleSYN supports the following versions of Microsoft Outlook:

Version 5:

  • Microsoft® Outlook® 2010 (32-bit/64-bit, Click-to-Run)
  • Microsoft® Outlook® 2013 (32-bit/64-bit) 
  • Microsoft® Outlook® 2016 (32-bit/64-bit)
  • Office 365® with Outlook®
  • Outlook® 2019 (32-bit/64-bit)

Version 4:

  • Microsoft® Outlook® 2007
  • Microsoft® Outlook® 2010 (32-bit/64-bit, Click-to-Run)
  • Microsoft® Outlook® 2013 (32-bit/64-bit) 
  • Microsoft® Outlook® 2016 (32-bit/64-bit)

Category: Troubleshooting, Version 4.x, Version 5.x

In this case there is an problem on the file "SimpleSYN.config", so SimpleSYN can not be started anymore.

To repair SimpleSYN on this computer, please follow these steps:

  • Open a Windows Explorer and navigate to this directory:

    For Version 4:

    For Version 5:

  • In this directory you will find the file: “SimpleSYN.config” (may also be shown as just “SimpleSYN” without the extension .config).
  • Delete this file
  • Restart SimpleSYN

Then SimpleSYN starts normally again. You would then need to activate SimpleSYN only once with your license file.

If you no longer have the license, contact our support.

Category: Installation, Version 4.x

In that case, you probably have an Office 365 version from the Microsoft App Store installed.

Programs from the Microsoft App Store can not currently recognize SimpleSYN version 4 (these programs are isolated from the rest of the system). Office 365 version from the Microsoft App Store supports SimpleSYN version 5.

Please reinstall Outlook / Office at

Then everything should work and go through the installation.

Category: Operation, Version 4.x, Version 5.x

If you want to exit SimpleSYN if Outlook is closed, follow these steps:

  1. Right-click on the SimpleSYN icon in the Windows notification area and choose “Exit”
  2. Close any Outlook window
  3. Open the SimpleSYN Add-In configuration file with a text editor like notepad. The configuration file can be found in:

    At Version 4:
    C:\Users\[User name]\AppData\Local\SimpleSYN\\[Outlook profile name].addin.config

    At Version 5:
    C:\Users\[User name]\AppData\Local\SimpleSYN\\[Outlook profile name].addin.config

  4. Add the following code in the section between <appSettings> and </appSettings>:
    <!-- SimpleSYN is exited when Outlook is being closed. -->
    <add key="AutoExitSimpleSyn" value="true" />
    <!-- SimpleSYN is started if the Add-In is being loaded. -->
    <add key="AutoStartSimpleSyn" value="true" />
  5. Open Outlook again.

Category: Operation, Version 4.x, Version 5.x

The SimpleSYN Business Version 4 installs a Windows service. If the option "Start as Windows service" is activated in the options, then SimpleSYN automatically starts in the background when the Windows starts, without a Windows user having to log on to the system.

The SimpleSYN standard version 4 and all older versions do not support Windows service. The synchronization takes place here only if a user is logged on to the computer and SimpleSYN is executed.

Category: Installation, Version 4.x, Version 5.x

SimpleSYN requires a unique configuration and a unique certificate for each PC.

SimpleSYN must be completely reset to one of the clients. Then SimpleSYN can be reinstalled and set up.

Follow these steps:

  • Uninstall SimpleSYN first under the Windows Control Panel "Programs / Features" or under Apps on Windows 10
  • Then enter the following line in Windows Explorer:
  • Find the folder SimpleSYN here and delete this folder.

Then delete the SimpleSYN certificate as follows:

  • Open the Internet Explorer
  • Go to "Internet Options"
  • Click the "Content" tab
  • Click on "Certificates"
  • In the next window under "Display name" search for the SimpleSYN entries, mark the respective entry and click on "Remove"

Then you can reinstall SimpleSYN and set it up again. The initial synchronization will be run once again.

Category: Troubleshooting, Version 4.x, Version 5.x

Please check the following things:

  1. Make sure, that you have not restricted the folders on your computers. You find this function on your client computer in the main window > synchronization settings > Advanced client settings. On your server computer you can find this function on the “main window > synchronization settings. Under “Available Folders” make sure that you have activated some folders
  2. Make sure neither Outlook nor SimpleSYN is started with administrator rights.
  3. Check if SimpleSYN and Outlook are using the same Outlook profile. You can see the Outlook profil in SimpleSYN in the main window > Options
  4. Make sure SimpleSYN is not started with compatibility settings enabled. To check this, right click on the SimpleSYN shortcut and select “Properties”. Click on “Compatibility” and remove tick in the checkbox “Run this program in compatibility mode”. It is possible, that this setting was somehow enabled during the Windows 10 upgrade.
  5. If you have multiple Outlook versions installed concurrently, select the right version in SimpleSYN under Options -> Advanced Options

Category: Troubleshooting, Version 2.0, Version 2.1, Version 3.0, Version 3.5, Version 4.x, Version 5.x

The message "destination folder was not found" appears if the top folder level in Outlook (eg "Personal folders") has been named differently on the SimpleSYN client and SimpleSYN server. In this case, SimpleSYN can not assign the destination folders automatically because no new PST files are created by SimpleSYN.

Click on the "Select a different target folder" link and select the folder where you want to sync.

Alternatively, you can name the highest folder level identically on all computers in advance.

Category: Purchase, Version 4.x, Version 5.x

You`ll need a license per computer you want to synchronize. 

For example: If you wish to synchronize Outlook between your laptop and your desktop computer, you will need two licenses. If you want to synchronize 3 computers, you`ll need 3 licenses, etc. If you want to use SimpleSYN on a terminal server with different users, you need a license for each user.

  • A SimpleSYN standard license costs 19.95 € per computer (including 19% VAT)
  • A SimpleSYN business license costs 34.95 € euros per computer (including 19% VAT

Ask about our discounts for school, university students, teachers and multiple licenses

Category: Installation, Version 4.x, Version 5.x

You can easily upgrade Outlook (Office). The previous version does not need to be uninstalled. SimpleSYN automatically detects the new Outlook version.

Install Outlook in the same bit version as the previous version, either in 32-bit or 64-bit.

If you want to install Outlook in a different bit version than the previous version, first uninstall SimpleSYN and reinstall SimpleSYN after the Outlook update.

Category: General, Version 3.0, Version 3.5, Version 4.x, Version 5.x

Press on your server computer inside of SimpleSYN’s main window once the “Alt” key to open the main menu and choose the menu item “View > State Properties.

If you open the state database properties (Tab “General”) on the server, do you see any old client that is not synchronized anymore (you can see this from the last synchronization date)? 

If yes, please click on this client and click on “remove”. This will delete the status for the selected client will make some space available in the status database.

Category: General, Version 3.0, Version 3.5, Version 4.x, Version 5.x

SimpleSYN can not be used to synchronize between a POP3 account and an IMAP account. Use the same account type on the PCs (either POP3 or IMAP).

If you use a POP3 account on all PCs, you can also synchronize the e-mail folders (for example, Inbox) with SimpleSYN.

If you use an IMAP account on your PC, then the e-mail folders are automatically synchronized by default, since an IMAP account is server-based. The e-mail folders of an IMAP account should therefore not be selected in addition to the synchronization, since otherwise it can lead to complications with SimpleSYN (as of version 5, e-mail folders of an IMAP account are also no longer selectable). If you use an IMAP account, SimpleSYN allows you to synchronize all other local folders (such as tasks, calendars, contacts, or notes).

Category: General, Version 2.0, Version 2.1, Version 3.0, Version 3.5, Version 4.x, Version 5.x

No, all of these devices are not supported by SimpleSYN.

SimpleSYN synchronizes Outlook installations with each other; a computer running Windows Vista (32bit/64bit), Windows 7 (32bit/64bit), Windows 8 (32bit/64bit) or Windows 10 (32bit/64bit) is essential.

If you wish to synchronize Outlook on your iPhone, Windows Phone or Android device, please contact the manufacturer of your device.

Category: General, Version 3.0, Version 3.5, Version 4.x, Version 5.x

SimpleSYN Standard is fully compatible with the Business Version. You can only synchronize over a local network with the standard version, however.

Please note: The SimpleSYN server has to be in the same local network as the client.

Further note: The Configuration Wizard in the standard version cannot establish a connection with the SimpleSYN server if the SimpleSYN server is configured for synchronization via the Internet.

Category: Operation, Version 3.0, Version 3.5, Version 4.x, Version 5.x

To call up the Configuration Wizard again, please follow these steps:

  1. Open the SimpleSYN user interface
  2. Press the “Alt“ key to show the SimpleSYN menu 
  3. In the menu under “Help” activate the entry “Show Configuration Wizard on next startup“
  4. Exit SimpleSYN. To do so right-click on the SimpleSYN symbol in the Windows system tray and choose “Exit”

The next time SimpleSYN is opened the configuration window will be displayed again.