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Throughout the day, my 3G modem will sometimes disconnect and reconnect instantaneously. If I happen to request a webpage at the exact moment the modem disconnects, Windows will cache the failed query and I can't visit that page without executing ipconfig /flushdns.

I have to do this about 20 times a day and it's extremely annoying. I edited the registry to disable caching failed DNS queries:

Name: NegativeCacheTime
Value: 0 (DWORD)

This seemed to work for a few days, but now Windows is caching them again. I've checked the registry and the value of NegativeCacheTime has not changed.

What's going on here?

share|improve this question
Seems like you're trying to turn on a flashlight with your nose. Fix the 3G modem is what I would do. – digitxp Sep 15 '10 at 1:53
There's nothing I can do about the 3G modem. It's a side effect of using mobile broadband in a rural area. Unfortunately, it's the only broadband I have access to. The reconnect is usually unnoticeable anyway, aside from the problem I outlined here, which is a Windows issue. – David Brown Sep 15 '10 at 13:42

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