A registry false positive (if you will).

The following item is detected as an Unused File Extension in ccleaner for those using Avira Antivir Premium

Unused File Extension {80b8c23c-16e0-4cd8-bbc3-cecec9a78b79} HKCR\{80b8c23c-16e0-4cd8-bbc3-cecec9a78b79}

When removed it causes no harm whatsoever and Avira simply re-adds the key (if you scan again the same key will be present).

Just wanted to let someone know so that it does not cause later confusion.

I figured this out by searching the key via google as well as uninstalling Avira to see if the issue persisted. It did not once uninstalled.

The following item is detected as an Unused File Extension in ccleaner for those using Avira Antivir Premium

Unused File Extension {80b8c23c-16e0-4cd8-bbc3-cecec9a78b79} HKCR\{80b8c23c-16e0-4cd8-bbc3-cecec9a78b79}

When removed it causes no harm whatsoever and Avira simply re-adds the key (if you scan again the same key will be present).

Just wanted to let someone know so that it does not cause later confusion.

I figured this out by searching the key via google as well as uninstalling Avira to see if the issue persisted. It did not once uninstalled.

I second this

Have a look at this discussion re the same issue:

http://forum.piriform.com/index.php?showtopic=21261

Hope it helps.

Thanks for the link, the solution given there works. However, it would be much easier if CCleaner just did a little adjustment in their code so when you do a scan for registry errors, the registry key in matter doesn't even show up.

With it being an important issue, I'm pretty confident this will be resolved in a future version.