Windows XP Professional Service Pack 3 was fairly stable, though it is way out-dated now.Windows Vista 32-bit Service Pack 1 seems to be good, but you really need current (faster, dual-core) processors and 3GB memory to work well with it.Windows Vista 64-bit Service Pack 1 actually seems to be better than the 32-bit version, but too many incompatibilities with programs and drivers, and it is really to get past the 3GB memory barrier in Vista 32-bit.So now there is Windows 7 Release Candidate, and I am testing the 64-bit version, which has been working surprisingly well.But with every version above, there has always been the random Windows Explorer issue that causes the computer to stop responding, and I do not understand why Microsoft has not corrected this yet.Though I will give Microsoft credit for at least allowing you to eventually recover from a Windows Explorer issue (if you wait long enough) in Windows 7 Release Candidate.Otherwise, Windows 7 Release Candidate has been impressively stable, though I am still waiting for the new Windows Security Essentials to be integrated within it.Anyway, if anyone has any ideas regarding the Windows Explorer issues in Windows 7 Release Candidate, where the screen just goes black for a long time with no response, then I would be very interested to learn about ways to prevent or fix it.Thank you.

Don,Have you downloaded any drivers or BIOS updates since installing Windows 7, or have you just let Windows update take care of it all?What do you have for a computer?

I seem to have a problem (Win 7 RC) with Explorer windows that pop-up when I try to do a "save as" from any of the Office 2007 tools. I can generally save if I accept the file name without any changes and also accept whatever folder it chooses to open it. If I try to change either of these, it frequently, but not always, hangs and shows as "(not responding)" and the only option is close or restart the program. It's happening frequently enough to be cause some concern...."save as" can be important from time to time after all!

Don - First off, the 32 bit OS RAM limit is actually 4 GB. However, Windows 32 bit (all versions) reserve a section of memory for hardware.. The actual amount of memory is determined by whatever hardware you've got installed.Secondly, it would help if you gave us more details as to what you're doing with Windows Explorer when it bombs.. Third - Microsoft Security Essentials - formerly known as Morro - is already working with Windows 7. Do not expect MSE to be included with Windows 7. It will be a stand alone product - much in the same way as Windows Live Essentials.

I have a similar problem. Frequently but not always, when I run a program which opens a dialog box to allow me to select a program to import, the dialog box will freeze and sometimes display 'Not Responding'. I am running Windows 7 RC on intel 64 bit and keep up to date with 'Updates'. I am using only the internal SATA drive and I have never seen anything similar before on Vista or XP.