I sent the messages below a couple of months ago, describing a problem that occurs with emacs on Windows 7. At that time, it was suggested that the bug was fixed in the new version of Emacs, so I didn't worry about it.
However, I installed version 24.1.1 a month ago, and after 452 hours of elapsed time, the same problem occurred again. Since then, I've also received a private message from another emacs user having the same problem. Emacs users on Windows 7 should be aware of this problem, so that they won't unnecessarily reboot their systems. ---------- *** First message I've used emacs on several different systems, including different flavors of Windows and xemacs on Linux, with pretty much the same macro set, which has been very convenient. I use multiple frames and multiple windows very heavily on a day to day basis. Starting late last year, I started working on a Windows 7 system, and emacs worked fine, as usual. However, after about 7-10 days of uptime, Windows 7 freaked out with all application windows blinking and moving around all over the place. At first I thought it was a Windows 7 bug, caused by one of my display settings, and I had to reboot the computer. But after it's happened several times over a few months, I've finally concluded that it's an emacs bug. It took me a long time to find this out, since the bug occurs so infrequently. Since I'm running 64-bit Windows, what it looks like to me is that emacs is using some 64-bit counter as a 32-bit or 16-bit counter that's cycling around to zero after several days of heavy use of emacs. Somehow, this is causing all the application windows on the screen to be screwed up or start blinking like mad. People using 64-bit Windows 7 should be aware of this bug, and be prepared for it. The workaround is to close and reopen emacs (you don't have to log out or reboot). This is a lot harder than it sounds, with windows freaking out and you can't find where your emacs window is. But if you can bring up the task manager, you can kill emacs. What I had to do was to create an abort macro, assigned to keystroke ctl-alt-f1, that creates a quick recovery file and exits. If you do that, then all you have to do is remember where your emacs window was, click on it, and launch the abort keystroke. Once emacs exits, all your other application windows are ok again. --- *** Follow-up message: Here are some additional details: * I'm using emacs 23.4.1 on 64 bit Windows 7. * I start emacs from a DOS command line batch file with the command "c:\xx\emacs-23.4\bin\runemacs" --no-splash --load c:\jx\emacs\init.el * The same problem occurred at another client with different application software running on a 64-bit Windows 7 system. (One used Visual Studio with C#, the other uses Eclipse with Java. I used Firefox on both systems.) * The bug has occurred about 6-10 times since last September. * I typically have 4, 5 or more frames open, each with two or more windows, so I'm a very heavy GUI user. * The bug never occurs in less than a week of uptime, and often not until two weeks of uptime. * On two or three occasions, the bug was triggered when I was scrolling through code. * It's the last three items that led me to propose that there's a 16-bit or 32-bit counter that's cycling around to zero. * I run emacs on another Windows 7 system that acts as a kind of server. The problem has never occurred there, which I attribute to the fact that it's a server, and the GUI is seldom used. * I also run the same version of emacs on a Windows XP system with no problems. --- *** Private message from another emacs user I saw your posting, and am running into an identical problem every week or so with emacs windows freaking out graphically but continuing to run otherwise. Just wanted to give you the details of my setup in case you got feedback from others to narrow down the problem. If you'd like any more specifics about my configuration, let me know and I'd be happy to provide them. Windows 7 64-bit Emacs: M-x emacs-version returns: GNU Emacs 23.1.1 (i386-mingw-nt6.1.7600) of 2009-07-29 on SOFT-MJASON Running dual monitors, Nvidia Quadro FX 1800, Driver version 8.16.11.9175 (ca. 2009) Also running another program linked against c:\windows\system32\GDI32.dll: Q-Dir 4.94 -- WinXp-like explorer clone that makes it a little easier to work under Windows 7. Not sure if these might be poorly interacting with each other. ----- John J. Xenakis GenerationalDynamics.com John J. Xenakis 100 Memorial Drive Apt 8-13A Cambridge, MA 02142 Phone: 617-864-0010 E-mail: j...@generationaldynamics.com Web site: http://www.GenerationalDynamics.com Forum: http://www.GenerationalDynamics.com/forum