Error while saving

Hello forum! I get "error while saving" when saving a composition in Fusion 8 beta. What can cause this?
https://forum.blackmagicdesign.com/
https://forum.blackmagicdesign.com/viewtopic.php?f=22&t=41607
Rony Soussan wrote:Mac or PC?
I know on the PC, you can't save to the install folder due to permissions in windows.
Does this happen to every comp?
Have you tried different drives?
Try setting comps to compressed, see if that helps (option in the global preferences)