Windows Explorer is restarting in a loop

Hi,
My windows explorer keeps running in a loop crashing and restarting. Any help? It happened when I tried to join a homegroup

You could try using a Windows 7 repair dvd / image
and use the repair options in there.

Or try malwarebyte

I've also heard that going to your registry (Win+R) RegEdit
And browsing to:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution.options

Then deleting explorer.exe and iexplorer.exe under this key works. But I personally don't know.
Best to make a back-up before doing this. Then you delete those two.
Restart your PC and fingers crossed.

If that did not work, restore your registry with the backup you made