During one recent Internet session with my HD-installed system, suddenly every time I right clicked the mouse a new Iceweasel window would open--no matter what the pointer was on. After rebooting a few times and experimenting, I realized that whatever I'd click on first would be the only thing the mouse would ever activate. The mouse pointer tracks normally and when "hovering" the text displayed is appropriate.
I rebooted and used the mouse to select console and ran a recursive clamscan of the home director from the command prompt with no result.
Then I hit upon the idea of changing the desktop environment from LXDE to KDE and the problem was fixed!... but only temporarily.
The first time I shut down the computer and rebooted the problem affected KDE. Now I can't even manage to change the desktop environment.
This is installed to the HD as I've mentioned and it is a dual boot with Vista... which I never use anymore except now.
It may not be related, but for some time now I've had an occasional problem of the windows losing their control buttons in the upper right corner; the minimize/maximize/go-away buttons. That would happen and I'd reboot and they'd come back.
Any ideas would be most appreciated! Thanks for reading.
I was going to ask if there was a console command for restarting/choosing the desktop but I managed to get to it; I had difficulty accessing it from the main window opened through clicking the KDE logo in the lower left corner, but managed to do so through the filemanager after hitting on the right combination of shift key+tab, space bar keys, etc. (I'm supposing that KDE's interface is affected in other ways than just the mouse but perhaps my unfamiliarity with KDE is in play.) Anyhow, I changed back to LXDE and all is working perfectly... for now. I'm expecting more trouble once I reboot and will follow up on this. Incidentally, I'm running Knoppix 7.04. Thanks!

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