my desktop background disappears after waking from sleep mode

I have the same exact issue, I have my external monitor hooked up, I just did a clean install of Lion, and now everytime I turn my monitor back on (sleep mode or no sleep mode) my wallpaper goes missing and its this bright GREY color. Help anyone?

(Mid 2009 Mackbook Pro)

Same here! Also have a Mid 2009 MBP running Lion (upgraded from Snow Leopard) connected to an external LCD panel via a DisplayPort/HDMi connector. Sometimes when it goes into sleep/lock mode, the backround will be grey once logging back in. A full log-off does bring it back again though.

Same here. I thought it had something to do with the second monitor since I don't recall seeeing it before I added it. No I'm not sure. Anyone know of a fix?

I think I was having this same problem and figured out that it had to do with itunes. After playing an itunes video in full screen and quitting a grey screen would cover my desktop and I couldn't view my wallpaper or desktop icons. Mission control was acting wierd as well. Anyways, if I quit itunes it solved the problem. Don't know if this is the same problem or not????

Same situation here. Rebooting "fixes" the problem but I left MS for Mac because I grew tired of rebooting to fix the problem!

Chrome isn't working properly anymore either. I really wish I hadn't upgraded SL was rock solid...

If you go into Terminal and type "killall Dock", the Dock and your wallpaper will disappear and then reappear, which fixed the problem for me.

Thank you! The "killall Dock" command worked like a charm. Much appreciated.

killall Dock does indeed work. Any idea why this is even necessary?

Just chiming in to report the same issue on a 2009 MBP. Killing the Dock process fixes it temporarily, but there's definitely a bug of some sort.

2011 MacBook Pro, originally with SL, but upgraded to Lion. Having exact same problem with iTunes. Run it in full screen mode and my desktop disappears. Close iTunes and it comes back.

Checked "Keep Mini Player on top of all other windows" in preferences and had been using a dual monitor desktop before it happened.

Also installed and then uninstalled InsomiaX and Caffeine (both of which mess with sleep settings) before hand.

Have no idea what the connection is if any.

I've been on the support line with Apple on this one and the person I spoke with reported hearing of this once before. My "gray screen" can be dispensed with by wiping my mouse back and forth over the screen (like wiping away steam from glass) and I can reveal my login icon. Irritating and I--like others--am struggling to know what my $$ purchased on this Lion upgrade.

Are you aware of any fixes to this problem? I'm having this exact same problem with my display. I'm running 10.7.4 on my late 2011 17" MBP and I have to use the mouse like a blackboard eraser in order to see my login screen. It only happens if I leave the display idle and it goes into sleep. If I close the top down, thus forcing it to sleep, the display is normal when I open the laptop.

Having exactly same problem. Genius suggested it had something to do with an app altering Dock so I trashed that (Docksomething). But didn't help so I reinstalled Lion (six hours) but it still happens.

Would relly apreciate anyhelp before I go bananas.

I spoke with Tech Support this morning. Apparently this is a known issue with Lion. I found it interesting that the rep insisted on saying that "it is the way Lion functions" instead of admitting that it is a GLITCH in the programming. He even said that it happens randomly and not on all computers and not all users experience this. That ought to tell you that it's a glitch. Anyway, there is a "workaround" which is what you do to put a bandage on a persistent wound that should really get surgically stitched:

You either have to log out every time you leave the laptop, or you have to change Energy saver preference to set the display to go to sleep AFTER the computer is set to log out (in Security preferences).

Here is the article that instructs us on applying the bandage::

http://support.apple.com/kb/TS4135?viewlocale=en_US

Suffice it to say that Apple does not plan on stitching this one up any time soon..

Many thanks.

However, on my machine there's no such thing on Security as mentioned in article and Display Sleep is tied to Computer Sleep so it can't go further without taking Computer Sleep with it.

So I'm testing putting Computer Sleep to Never and hoping this will work.

Does this make sense?