Hi nhebert,
All computer monitors, whether they are LCD or CRT style, have a built-in feature called the on screen display (OSD) lock out that prevents users from viewing any images on the monitor. If your computer screen has accidentally been set to the OSD lock out setting, there are several different ways you can remove the lock out, depending on the make and model of your particular computer monitor.
Here are the steps that you can try to get rid of the little white box “OSD lockout”.
1. Power your computer completely off and then remove the monitor cable from the port on the back side of the computer case. Reattach the cable and make sure the pins are correctly screwed in all of the way. Power the computer back on and check to see if the OSD lock out message is still being displayed.
2. Check the manual that came with your computer or monitor and locate the troubleshooting section if you are still receiving the OSD lock out message. Find the OSD lock out heading and read the method that your particular model of monitor uses to remove the lock out. Follow the instructions to remove the lock out.
3. Attempt generic lock out removal procedures if you no longer have the manual that came with your monitor. Press and hold the "Menu" button located at the bottom end of your monitor for 15 seconds and wait to see if the OSD lock out message disappears.
4. Press the "Menu" button again if the lock out message remains on the screen. Use the arrow buttons to navigate through the main menu options. Highlight the "Settings" or "OSD Menu" option and then hit the Menu key again to access the new list of settings.
5. Scroll down to the "OSD Lock" heading. Use the arrow keys to change the setting to "No." Hit the Menu key again to return to the main menu. Scroll over to the "Exit" setting and then hit the Menu key a final time to exit the menu setting and remove the OSD lock out.
After getting rid of the message, check if you’ve sound on the computer. If you still have no sound on the computer, I would suggest you to try the fix it tool from the link below.
Tips for fixing common sound problems
http://windows.microsoft.com/en-us/windows-vista/Tips-for-fixing-common-sound-problems
Post your results back about the status of audio on your computer.
Regards,
Mouneshwar R – Microsoft Support
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