I got this message too and for sure before V4 came out. I also think it has to do with the update function. If I go into the General Preferences --> Misc and click the 'Check now' button I get that error message each time. I didn't see any problems resulting from this though.

But I have a really bad problem now with my saved V4 scenes I did so far. It's impossible to load them again. Got exactly the same problem as Neyjour described above. :(
I found out that when I do a 'File' --> 'Close' or start Poser 6 new and don't try to load a V4 scene I can at least load my old files not containing V4.