upgrading unity SAFE?

Will my project be changed if i upgrade from unity 4.0 pro to the latest free version ?, i mean will any scripts dettatch themselves, will all my prefabs stay the same… etc
if so:
Is there something i can do to prevent this happening.

I have never upgraded to 4, but I have upgraded v3.x about 4 times and there have been no mixups etc.

What do you mean, “upgrade from unity 4.0 pro to the latest free version”? If you have a Pro license, then you have Pro for all of 4.x. In any case it doesn’t really matter if it’s “safe” or not…if it doesn’t work for some strange reason, just restore your project from backup and go back to using the old version.

–Eric

(Maybe it was a Pro trial, or, cough, a non-legit version.)