|Using my virtual computer, I ran two tests. The first was the default installation options, which set Opera as my default browser. After installing, I noticed my HTML files got the Opera icon too. I opened up Revo Uninstaller 1.92 Free and set to uninstall Opera using the Advanced mode. When the Opera un-installation wizard popped up, I checked "Delete Opera user data". Then I clicked Details and verified all the options were checked. The Opera wizard completed and Revo moved on.|
While scanning for leftover data, Revo found a total of 149 leftover registry entires/directories spanning across 3 hives: hkey_classes_root, hkey_current_user, and hkey_local_machine.
In the Classes_Root hive, there were sub-directories for various file types like .htm, .html, .mht and some Opera-specific ones. Those are all good to delete and where the problem lies.
The Current_User hive had 5 keys and 1 registry directory referencing files in the C:\Program Files\Opera folder, so all those are safe to delete.
The Local_Machine hive had 1 entry called "Opera Software" which is also safe to delete.
So it looks like Revo did a good job identifying registry files. On the Registry removal screen, you can click the Select All then Delete buttons and move on.
Revo also found two leftover Opera files/folders, one was a file in the Opera program files folder and the other was the Opera program files folder itself. Delete 'em both.
After Revo finished, I noticed some web files still had the Opera icon and other web files had the "blank icon." So I opened my favorite web browser (Firefox) and used the "Set Firefox as default browser option." Afterward, my icons changed to the preferred Mozilla icons.
For my second test, I unchecked the option to make Opera the default web browser. Before you click the "Accept Terms & Install" button, click Options and un-check "Use Opera as default browser." After the install, my icons didn't change to Opera icons.
I followed the exact same steps to remove Opera with Revo and this time it only found 7 registry entries. None from the Classes_Root hive. The other two hives had the exact same entries listed, so they were removed. The files/folder step also found the same 1 file and 1 folder, so they were deleted.
With the process complete, my icons were just as they should and I didn't need to set another browser as default.
In summary, Revo did a great job identifying registry keys to delete, so it's safe to delete all that it identifies. Thanks to my test, I remembered that Revo also creates a System Restore point before removal, so you're pretty safe if there is a problem. A Restore point includes a registry backup.
If you set Opera as default during install or anytime during it's use, it will change the file icons. So after uninstalling, open your favorite browser and set it as default, and that will fix your file icons.
If you never set Opera as default, you won't have the web file icon problem.
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