To solve the 1899 dates in Softlog Manager update the Softlog controller service to SLControllerSvc 3.29.0 or newer.
File can be requested from firstname.lastname@example.org.
Steps to update.
Stop Softlog Controller service under Windows services.
Brows to C:\Program Files (x86)\Softlog\Server\Controler
Rename old SlControllerSvc to .old
Copy new SlControllerSvc to C:\Program Files (x86)\Softlog\Server\Controler
Start Softlog Controller service under Windows services
If you still experience the 1899 dates after the update double check the advanced settings on workstations. under Regional Settings.
Decimal symbol must be"."
List seperator must be ","