Vues :

The mails in the different mailboxes are not being processed even if the Background Process Service is up and running.

Please check the Connect to Mail log and search for error messages first.
The log can be found in %allusersprofile%\DocuWare\Logs\ConnectToMail.

In case there is a message reporting the following errors:
"Unable to logon to DocuWare Platform. Invalid DocuWare Platform login token for this user
If you have changed your password please login to DW webclient settings and re-save your mail connections."

"ClientProtocolManagers are not specified"

please check if the file %allusersprofile%\DocuWare\ServerConfig\DocuWare.PlatformModel.settings exists and if it contains the correct information regarding server and port in line
"<ConnectionSettings Name="Standard AS" Server="ServerName" Port="9000" Local="false" Active="true" System="Central system" />"
If the file does not exist, please copy it from another running system and adapt server name and port if necessary.