USB keyboard and mouse not working after login

[drone1010]

I have a Dell 560s which is about 2 years old. I turned on my PC today and realized that the mouse and the keyboard weren't working. I tried many times in normal and safe mode - no changes. The keyboard works in the BIOS but all the lights on it go off after the computer starts loading windows (when the screen says "Starting windows"). The laser in the mouse also goes off after this point. The computer runs Windows 7 Home Edition. Please help ASAP! Thanks in advance

 

[soundguruman]

The power management settings are turning off the USB devices to "save power."
This is a long standing bug that has never been corrected.
Also certain "updates" may have reconfigured your power management settings. Certain "automatic updates" are non-compatible with all computers, and should be avoided.
You might be able to use a non-usb mouse and keyboard to reset the power management settings.
un-check the boxes that say: " allow windows to turn off this device to save power." It's located in power management.

BUT there is hope. In case an "automatic update" has rendered your computer UN-useable, as above, you can load the windows 7 disk in the drive, select "update." The "update" sets the OS back to default, but does not erase your personal files and programs.
Then you can shut "automatic update to "OFF." Then ONLY install the critical updates manually, avoiding updates that cause problems, such as, reconfiguring your power management settings.
The update problems only happen on "some" computers, and not ALL. It may corrupt your video drivers, disable your audio, disable your CD / DVD drive, and several other bugs, as above. Many users continue to experience these problems, but the manufacturer does not address the problems.
And so, several of us are left to fend for ourselves, and have created our own solutions, because we do not get the support we require.

 

[Onus]

When they are non-functional, another frequent fix is to unplug them, then re-plug them into the same jack. You'll hear USB tones as they reconnect, and they should work again.
But yes, adjusting power setting should prevent it in the first place.

 

[drone1010]

I tried the things that have been mentioned. Anyway.... they did not work. The only solution which popped in my head was restoring the computer to a previous good configuration - I thought it was, most probably, a virus or something of that sort. So I have restored the computer and solved the problem! .... Thank you for the help!