Let’s try setting program access and computer defaults to Microsoft Windows:
1. Open Set Program Access and Computer Defaults by clicking the Start button , clicking Default Programs, and then clicking Set program access and computer defaults. If you're prompted for an administrator password or confirmation, type the password or provide confirmation.
2. To specify the default programs for activities such as browsing the Internet and sending e‑mail messages on your computer, choose one of the following configurations, expand the configuration and choose options (if available), and then click OK.
You can also try System restore to a point in time prior to the problem. I hope this helps.
Lisa
Microsoft Answers Support Engineer
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