Thanks everybody for all the suggestions. Maxim --- thanks for bringing up Ctrl+Alt+F1 followed by Ctrl+Alt+F7.
Although it did not fix my problems, the Ctrl+Alt+F1 brought up a new terminal and so proved that there was nothing wrong with my hardware and nothing wrong with the keyboard software. Ralf thanks for pointing out the locking script and xset, and Petter thanks qualifying this with the DISPLAY info. I tried forcing dpms on and off, and in fact looked at the man page for xset and tried a bunch of variations, but none of these worked. Janusz --- thanks for the suggestion about the power switch. I thought it just might work, because usually i have to press and hold the power key for several seconds to bring the machine down. That suggests that the software has a chance to discuss things with the hardware before anything happens. However this time, when i just briefly pressed the switch, it actually powered off. (But the power off was not immediate, so something was presumably happening.) And that ended the experiments, because i cannot reproduce this error condition at will. If i just lock the screen, and then immediately unlock, i don't have issues (except for losing the cursor). So i have not yet had a chance to try Petter's suggestion of restarting the lightdm.service. I hope to try that the next time i'm in this situation and will report the results then. Thanks again everybody! dan -- xubuntu-users mailing list [email protected] Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/xubuntu-users
