Depending on the amount of songs you have, and how fast your computer is this process can take from 30 seconds to 15 minutes.For my little 429-track library, it took less than 2 minutes, which is quick keeping in mind that ) are tagged with album art and all other information.
Windows media player updating media library
To start, Click the Windows Start Menu Orb and Type in the search box. From the Services window find the Windows Media Player Network Sharing Service. A small dialog box may temporarily appear while the process is stopping.
Keep the Services window open; we’ll need it again, later on, to re-enable this service after we first eliminate a few files.
Manually Entering Metadata If your search for the correct media information comes up empty, you can always manually enter the information yourself.
On the Find album information window, click Edit under Existing Information.
(Warning – there are several Local MLS_*files, make sure to delete them all!