Cubase 5; all insert effects on a track is suddenly gone

Cubase 5.1.1 - 32-bit
Windows 7 - 64-bit

Greetings everyone! So, my Cubase started doing something weird recently. When working on projects, using different insert effects, like reverb and delays, on various tracks - some of the tracks will be “reset” the next time I open the same project, even though I saved it. Meaning that all the insert effects are gone, and the volume is back at 0.00 dB. It only happens to a few of the tracks, sometimes 3-4 tracks, and it’s mostly affecting tracks with reverbs and delays. The standard RoomWorks reverb for instance.

This is extremely frustrating when you’re looking forward to check out the perfect mix you just did yesterday, and everything is now screwed. - Has anybody experienced this? And more importantly; does anybody have a solution for this kind of problem?

NO ONE Know This?..My Inserts are GONE everytime I open my projects!?
I saved everytime! And still happened…