Save in game no longer possible

[LonewolfGer]

Hello everybody.
First apologies if the English version is not 100% correct but I'll translate that with the Google translator.

Have LnL HoS installed on my new PC, operating system is Windows 10. The game runs flawlessly, also the latest version is installed. Only I can not save now during a mission. If I click Save, then enter and save the save name, no save file will be created. Did you have the problem synonymous and if so how can you fix it?
Had this Game then played on my Windows 7 Pc and I did not have the problem.
Have the game run as an administrator without success.

Hope somebody can help me.

Thanks