Thanks for your answer. I already tried it and no more luck.
After checking, it seems this has nothing to do with the Windows 10 preview. I linked my PC to a professional account at the same time.
This means I now have a personal (live ID) account, and a professional (Office 365) account both linked in the same Windows 10 login. When I choose OneDrive sync in Enpass, I'm automatically linked to my professional OneDrive account, and the application is then not able to find any data because they are all in my personal OneDrive account. If I unlink my professional account in the Windows 10 parameters of the session, everything is working fine again because I'm automatically linked to my personal OneDrive again.
Is there any way to force Enpass to use my personal OneDrive instead of my professional one when I choose OneDrive sync in the options?
Thanks for your help.