Windows workstation has joined to windows domain. Following Group Policies are set:
Folder Redirection policy processing
Group Policy slow link detection
Also: User Policies\Windows Settings\Folder Redirection\Documents is enabled so that "For user Clair, this folder will be redirected to: \\STORAGESERVER\SHARE\Clair\Documents"
Result is that My documents is no longer "normal" directory, but a network share. Arma3 is unable to handle saving data to it's profile directory, which is located under My Documents. Same thing will happened with Arma2OA