After some malware cleanup and a bigger battle to get the antivirus AVG uninstalled from a computer, the last remaining symptom was a message shortly after launching Internet Explorer. It stated:
Internet Explorer – Search Provider Default
A program on your computer has corrupted your default search provider setting for Internet Explorer.
Internet Explorer has reset this setting to your original search provider, Bin (www.bing.com).
Internet Explorer will now open Search Settings, where you can change this setting or install more search providers.
Unfortunately, the solution wasn’t as simple as IE’s reset or choosing a new search provider and making it the default. Even upgrading Internet Explorer 8 to version 9 still resulted in the same message.
Fortunately, the solution was able to be found on a Microsoft Answers thread. The trick is to delete a cache file that IE uses for the search history that must have become corrupted or at least no longer lined up with IE’s actual settings.
Step 1: Close Internet Explorer.
Step 2: Browse to C:\Users\User\AppData\Roaming\Microsoft\Protect
Step 3: Hit the Alt key to reveal the menu bar and go to Tools, Folder Options.
Step 4: Choose to show hidden files and uncheck to Hide protected system files under the View tab.
Step 5: Delete the CREDHIST file.
Step 6: Reset step 4 back to how it was.
You can now launch Internet Explorer and ensure that the error message does not appear. The CREDHIST file is recreated if it is missing the next time Internet Explorer is running. It just isn’t corrupted from the previous junk the next time.