It looks like the Microsoft Wireless Laser Mice (or their receivers specifically) are causing a number of problems related to timing and timeouts that some applications use.
As loyal readers know I’ve been struggling with a few issues in Visual Studio 2005 in relation to Intellisense not working correctly with ASP.NET pages and it looks I’ve now finally found the culprit – it’s my Microsoft Wireless Laser Mouse (Mice actually - I have two of them and they both exhibit the same behavior). As soon as I unplug the laser mouse Intellisense starts working correctly – plug it back in and it fails. I use a KVM switch with another desktop machine, and this was the reason BOTH of the machines were apparently having the exact same issue. I dug out an older wired Microsoft USB Optical mouse and now both machines are happy with Intellisense.
This was a bitch to catch because at various times I thought I had discovered the source of the problem (keyboard programs like SlickRun and nVidia were both false alarms)... most likely I just happened to have my laptop disconnected from keyboard and mouse at the time when it worked. As soon as I plugged back into the KVM the problem returned.
What's interesting too is if I have the Laser Mouse plugged into the KVM, it would fail even if the KVM switch is pointed at the other machine! Somehow Vista is still seeing the device even though it's not directly connected (you hear the USB 'disconnect').
With the wired mouse there are also other problems which have now also been solved: The machine did not want to go to sleep on a timeout schedule. Ever! Apparently the mouse is sending some sort of action signal that keeps the machine from going idle. Not only that, even when I did send the machine to sleep explicitly it would invariably wake back up a few minutes later. If I wanted the machine off I had to explicitly Hibernate the box. All of these issues are history now.
I’d be curious to hear if others running the same mouse hardware are seeing similar things.
Chris’ post seems to indicate that this is an issue on XP too, but I can no longer check for that since I don’t have an XP box handy here (other than Virtual PC which doesn’t count <s>). On my machine there’s no ehtray.exe running...
Hopefully this will get fixed by Microsoft at some point...