Windows 7: Space bar wake from sleep issue

I have a Logitech USB keyboard. Since I installed Windows 7,I could wake the computer from sleep by pressing the space bar. About 3 days ago that function no longer works. I have to press the power button in order to wake the computer. Would like to go back to using the space bar, any ideas why and how to fix this? Thanks

Go to Device Manager > Keyboards (double click) > your keyboard (double click) > Power Management tab > tick the box where it says: " Allow this device to wake up the computer".

I don't have that option given to me. At one time I did see that option but now it is not there....?

What don't you have - the power management tab or the box to tick (is it greyed out?).

The only tabs are"General""Driver"and "Details", there is no"Power Management "tab shown.

That is strange indeed. Try "Mice and other pointing devices" - maybe you have more luck there. Then you can wake the computer by moving the mouse.

Same thing there. Thank you for your time. Some info. A few weeks ago the scroll wheel on my mouse quit working. Logitech sent me a new keyboard and mouse under warranty. I replaced the mouse. All was as before, the space bar would wake from sleep. Then I thought why not use the new keyboard. So I replaced it with the new one. Thats when I first noticed this issue. Also the new keyboard had an issue with the space bar "sticking". I looked into the "Device manager" and it did have a tab for "Power Management" and it was enabled for the kboard, but would not wake the computer. I then decided to go back to the original kboard. For 2 days it worked as before the space bar would wake it from sleep. All seemed fine. Today the problem returned and now in Device manager there is no option for "Power Management" This is strange.....??

Strange indeed. Did you get a driver CD with the keyboard or are you running on a generic driver.? Maybe you should reinstall the driver.
Also, again in Device Manager, check the USB hubs - they are usually the very last entries in Device Manager (you probably have 2). See whether you can enable it there.
But if none of that works either, I am out of ideas - sorry.

I think I fixed it! Used your suggestion of looking at USB Hubs. Confusing ,there are 22 listings there! Any way I then remembered I have the following USP ports on the computer. 2 on the front, 4 on the rear(on the motherboard) and I installed a 4 port hub in the PCI slot. When I put the mouse or kboard in the 4 port hub, I have this problem,BUT when I use the motherboard USB hubs everything is fine. When connected to the motherboard hubs there is a tab for powermanagement and now all is working again! why wouldn't the 4 port hub connection display the pwrmngmnt tab? Anyway thanks for your time, I really appreciate it! now I will try to figure out that 4 port hub thing.

Aha, you never said anything about the additional hub - but so what. You got it running and that is what counts. Have fun with your regained freedom - LOL.