Hi I'd try a system restore if it happened recently restore to just before the problem

Use System Restore

After you've decided to use System Restore to revert your system to a previous state, start the System Restore Wizard and follow the prompts. To use the System Restore Wizard, make sure you're logged on as an administrator, and then follow these steps:
1.
Click Start, point to All Programs, point to Accessories, point to System Tools, and then click System Restore.
2.
On the Welcome screen, click Restore my computer to an earlier time, and then click Next.
3.
On the Select a Restore Point page, select the date from the calendar that shows the point you'd like to restore to, as shown in Figure 2, and then click Next.

Figure 2

4.
On the Confirm Restore Point Selection page, verify that the correct restore point is chosen, and then close any open programs.
5.
Click Next if you are ready to proceed or click Back to change the restore point.
6.
The computer will shut down automatically and reboot. On reboot, you'll see the Restoration Complete page, and then click OK.

Hey, uhhh

i always thought that system restore restores files etc but not registry

obviously i learnt wrong

Glad I Learnt Something New