I set up a new PC recently and installed Windows 7 Pro. Approximately once every few days I get a problem which, oddly, has several seemingly different manifestations. I mean that if I see one of these, all the others can be observed as well, until I reboot. These manifestations are:
- Windows Media Player will not play an audio file (.wav, .mp3), usually just hanging. VLC player will not hang but will not produce sound either. Video content is played OK though.
- Explorer (if started by left clicking on the toolbar button) will bring up the message “Invalid signature” and won’t start. If started by right clicking and then selecting one of the folders in the “last used” list it will start OK though.
- Computer – Manage will dim screen and display a UAC message (normally it would start straight away). After getting through this message, the “Computer Management” window will duly pop up, but it will be missing the Event Viewer item in the left panel.
I could find nothing suspicious in the event logs.