I've downloaded the installer for Activesync 4.1, but haven't opened it yet. Does anyone know if that solves any of the synchronization problems? I am like the Titanic right now ... unsynchable. Does it have any new problems that 4.0 doesn't?

I installed it and, while still not perfect, have much better success.

"...titanic... unsyncable..!" LMAO ha ha ha!
liked that one..!
i wish to upgrade to 4.1 however there seem to b known issues with this release.
microsoft site itself is the place where i found that... so be weary of this 1 till it is stabilized a bit!

I upgraded from 3.8 and it was a mess. I couldn't connect. The big problem is that after you upgrade, if you try to uninstall, several files are not taken away which have later release dates. When you try to reinstall 3.8, Windows doesn't change those files, so 3.8 doesn't work. It took forever to figure out that I had to delete all the files (located in windows/system32), uninstall, reinstall...I would advise to wait for the official release...

Unfortunately, 3.8 isn't a choice for me, as my IPaq has Windows ce 5.0 which won't work with releases earlier than 4.0. I was hoping 4.1 would include the promised fix, but I installed it and notice no difference.