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after using Emacs for a while, I frequently encounter hangup issues, e.g, when I try to move the cursor, the software just freezes for ~5 second before it can response.

I then used the Process Monitor from M$ to check what is wrong, and I believe I found something but just don't know how to solve it. the operation that causes the issue is:

RegOpenKey by emacs.exe, which is searching for a key in registry 'HKLM\SOFTWARE\Wow6432Node\Microsoft\CTF\KnownClasses', but NAME NOT FOUND

since there is no such key, i just added manually, and then the issue becomes:

RegQueryValue by emacs.exe, which is searching for a key in registry 'HKLM\SOFTWARE\Wow6432Node\Microsoft\CTF\KnownClasses\Emacs', but NAME NOT FOUND

Has anyone here know what is the root cause of this? or how should I add keys in registry to solve the issue? thanks

share|improve this question

As always...

Can you reproduce the problem starting from emacs -Q, i.e., with no init file (~/.emacs)?

  • If so, great. In that case, consider sending a bug report to Emacs Dev: M-x report-emacs-bug. It is not normal for Emacs to hang.

  • If not, bisect your init file recursively (e.g. commenting out 1/2, then 3/4, then 7/8, ...) until you find the root of the problem. Then report that code here if you still have a question.

share|improve this answer
its not reproducible... sometimes i work days with emacs, and nothing happens, sometimes, from no where, it just happens... That is why i use process monitor to check what is really causing the problem, and found this registry issue in windows. – shelper Nov 26 '13 at 22:05

I have the exact same issue - not with Emacs, but with OllyDbg.

As soon as I installed Visual Studio 2013 on my system, halting at a breakpoint in Olly freezes my PC for about 5 seconds, keyboard input is impossible, moving the mouse is ok, but clicking causes beeps and fills up the message buffer.

After the 5 seconds, the pressed keys are all sent at once to whatever became active.

Also, ProcMon showed

RegOpenKey HKLM\SOFTWARE\Wow6432Node\Microsoft\CTF\KnownClasses NAME NOT FOUND

as the last entries of interest. After that - 5 seconds of Process Profiling, but not a single event.

My whole system hangs, the task manager, if I can even open it, doesn't even show processes anymore. This is a serious bug if you ask me.

I have not yet really found an answer here, but a possible solution would be: Do you also have Visual Studio installed? Try uninstalling it.

share|improve this answer
the issue has gone for a while... i dont know if that is VS, I still have VS installed but haven't use it for months – shelper Oct 10 '14 at 23:22
Interesting! VS causes the exact same problem to me in any debugger (not just Olly). Have a topic here and on, no answers :/ but thanks for the update. – Ray Koopa Oct 10 '14 at 23:23

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