Hello,

Try to install latest update for WinCC flexible 2008 SP5:

Update (Hotfix) for WinCC flexible 2008 Service Pack 5

Best regards,

Wizard

Hello VinBor

you can try to find out with which Version The Project was opened the last time:

Open the*.hmi file with a text editor (for example Notepad). Then search for "Edition:" 

you should be able to see every Version from the editin history. the newest Version should be the last that was used.

Bye Murof