Thumbnail Server does not start

Behavior:
Thumbnail Server does not start.

Solution:
Please check the following steps if Thumbnail Server fails to start:
(Check after every step if Thumbnail Server starts)

1. Check if Thumbnail server was registered.
   Check in DocuWare Administration whether license information is displayed for Thumbnail Server (DW Administration -> Organization-> General -> Licenses -  Server Licenses).
   If no license for Thumbnail Server is displayed, the license has to be installed again (right click on License and install License file).
    
2. Check the table dwserver in the database (in dwsystem > tables) if there is an entry for Thumbnail Server.
   If not, Thumbnail Server has to be uninstalled and installed again using DocuWare Setup.
    
3. Check in the database if a dwthumbnail database exists.
   If not, it has to be generated manually (Right click on Databases > New Database > Set database name "dwthumbnail").
    
4. Check in DocuWare Administration if a database connection to the dwthumbnail database exists.
   (DocuWare System > Data Connections > Database Connections) and check with the button "Check accessibility" on the tool bar if the connection works correctly.
   1. If database connection to dwthumbnail does not exist, it has to be generated manually:
      (Right click on Database Connections > Create New Configuration > Type in "Thumbnail Connection", Used for: Thumbnails, select database, database Server Name: Servername of the located database, database: dwthumbnail, Username and password to login on database).
      After manual generation of the database connection, check with the button "Check accessibility" on the tool bar whether the connection works correctly.
      After generating the database connection "Thumbnail Connection" it has to be assigned to Thumbnail Server (Server > Thumbnail Server > Area General > Select "Thumbnail Connection" for field Database connection).
   2. If the connection does not work correctly, it has to be checked if the parameters typed in the database connection are correct:
      Check the database server name (test also with parameter "localhost") and the login parameters for the database. Check with the button "Check accessibility" on the tool bar whether the connection works correctly (connection data correct).
       
5. Check in the installation path of Thumbnail Server if the file DWThumbnailService.exe.settings exists and the entries are correct.
   Edit the file DWThumbnailService.exe.settings and check if Servername, Organisationname and GUID of Thumbnail Server are correct. The GUID of Thumbnail Server must be the same as the GUID which is displayed for Thumbnail Server in the table DWServer on the database. Change the entries in DWThumbnailService.exe.settings if they are not correct.
    
6. If Thumbnail Server Service does not start with the assigned user change it to the local system account.
    
7. If Thumbnail Server does not start, check if any error messages are generated for Thumbnail Server in the event manager in section Windows Logs > Application
   • If the Windows event log shows the following message: "ThumbnailServer::Error: Invalid switch security channel name. Channel <NotSecure> do not exist in appicaton settings file   at DocuWare.Remoting.SwitchChannel.SwitchProviderChannels.GetChannels(String name)"
     please follow the steps below:
   1. To start Thumbnail Server again, please stop Thumbnail Service first.
   2. Afterwards, DWThumbnailService.exe.settings needs to be modified. (You can find this file by default in the directory C:\Program Files (x86)\DocuWare\Thumbnail Server.)
   3. Change the parameter "LoadCommunicationOption" from „true“ to „false“.
   4. Then copy the line
      <SwitchSecurityChannel Name="NotSecure" Active="true" />
      and paste it above the line
      <SwitchSecurityChannel Name="SSPI" Active="true">.
      This modification needs to be made for two positions.
   5. After that delete the line <SwitchSecurityChannel Name="NotSecure" Active="true" /> from its original location.
   6. Additionally, the SSPI Channels must be set from „true“ to „false“.
      For an explanation please have a look at the screenshot below:
      
       
   7. After saving the file, please start Thumbnail Server again.
       
   • If the Windows event log shows the following message: "Cannot find table dwthumbnail/dwfcmap from the internal data dictionary of InnoDB through the .frm file for the table exists."
     Please delete database dwthumbnail and create it again manually. Thumbnail Server will start correctly afterwards and create the needed tables itself.
       
   • If there is another error message shown in the event log please send us the exported event log (.evtx)