Flashbuilder 4 beta 2 runs fine on windows 7 x64, there is a possibility that your install is corrupt, one thing you can try is see if you can extract the install set from the download, you can do this by opening the download exe with something like 7zip. You then try installing directly from the extracted flashbuilder install set.
I tried this, thank you. It looked hopeful, but I have exactly the same problem. There is definitely an issue on this W7-64 PC...
One other thing you can try is to run win 7's xp mode and install flashbuilder in the xp vrtual machine.
I'm running fine on Windows 7 x64 as well. Perhaps it's a Windows User Access Control issue? Have you tried to run as administrator?
Jason San Jose
Quality Engineer, Flash Builder
Yippee!! I happened to unplug my USB backup drive between restarts, and now it works. At least, that's the only difference....
That was weird.
Thanks for your help !