thanks tcmusic and BBB....as you have probably already firgured out, r4 was one of the VST "revisions"--this number is usually found after the second decimal point in the "version" description of software....CuBase always advises to check with their site regularly to download the latest updates and fixes...they even have a cd burner update--if your burner is on the list....yes BBB, I have noticed problems with the restore function--it did fail to work on one occasion....I wish that were the sum of it....right now, using r5 I am getting "a serious problem has occurred" messages whenever I try to open or close a .arr file....nothing drastic occurs as a result, but, it won't open .arr files....the .all files work fine and always "open" to the last "arrangement" (eq, effects, tracks) I was working with....for a couple of days I thought my problems had gone away--as a result of uninstalling WAVELAB--but then I had another lock-up while on the net and the "serious problem has occurred" messages continued upon exiting or opening a .arr file (these messages make no mention of exactly what the the problem is)....I have not ruled out the possibility that ME is the cause of the lock-ups while net-surfing....actually, CuBase has only locked-up (unresponsive) the computer a few times--first, when I tried to get Free-Filter to perform the Learn function, and then a couple of times upon exiting what I presume VST recognized as an "arrangement".... after reading your replies, it is apparent that ME has some problems of it's own--I encountered a crash while on the net when Cubase wasn't even on my computer....thanks BBB for the details, and I'll try reducing the Restore function right away, but, I'm afraid that I'm not quite ready to disable it--I need the safety net....I'll keep you guys posted and please do the same....later, dean.