One thing that I have noticed when this happens is that I can barely see the top of the taskbar at the bottom of the page, with the top of the first row of tasks just barely showing. I do not use any third party screen savers (never have), and do not have
auto-hide checked. Windows 7 is the only version of windows where I have had this happen, and then only on a laptop with an extended desktop across two monitors. The only thing I have found that works so far is the script for killing and restarting explorer.
It happens so much that I have one of my Favorites keys on my MS Natural keyboard set to execute it.
Opus 13 - What a pain in the **** this is for everyone. Have you tried making the setting change I suggested? Since I changed mine my taskbar has not disappeared in over two weeks! Here's what I did.
Go to 'Control Panel'
Hit 'Hardware and Sound'
Hit 'Power Options'
Hit 'Change When the Computer Sleeps' (on the left side of the screen)
Change the 'Put the Computer To Sleep' under both 'On Battery' and
'Plugged In' to "Never"
Hit 'Save Changes'
My taskbar was present when I changed this setting. Get the taskbar back before you change the setting. Re-start if you have to and you will probably have to re-start after you change the setting but it is worth the effort.