Why have some of my Desktop icons changed in appearance?

Q I downloaded Service Pack 1 for Windows 7 SP1 and, as a result, around a quarter of the icons on my Windows Desktop have lost their original design. I have restored the computer to its previous state but those icons have remained incorrect. Any ideas please?
Sam Sweet

A We reckon there are a couple of possibilities here. Either your Windows user account has become corrupted or a similar fate has befallen something known as the icon cache – a file that Windows draws on during start-up (and other times) to display the program icons.

Luckily, both can be fixed, though repairing a corrupt user account is considerably more complicated, so fingers crossed that it is the latter that’s gone wrong here.

Fixing the icon cache is pretty straightforward and involves deleting a hidden file that acts as the cache. The absence of this file when Windows is restarted causes the operating system to rebuild it from scratch, curing the corruption.

To do this, first ensure that no other applications are running. (Indeed, though not essential, it is best to first launch Windows in Safe Mode – to do this tap F8 soon after the PC is switched on and then select Safe Mode from the displayed menu, using the cursor/arrow keys to move the highlight up and down and Enter to select.)

Now launch Windows Explorer (pressing the Windows key and tapping E is a quick way to do this) and then click the Organize button at the top left and choose Folder and search options from the dropdown menu.

In the Folder Options dialogue box that appears, click the View tab and then scroll down to find the ‘Show hidden files, folders and drives’ radio button – click to select it and then click OK to close Folder Options.

Now use Windows Explorer to navigate to C:\Users\YourWindowsAccountUsername\AppData\Local (replacing ‘YourWindowsAccountUsername’ with your own username), where you should find the icon cache file – it is called IconCache.db.

Click to select it and then either right-click and choose Delete or press the Delete key on the keyboard. Read the Delete File warning to ensure that you are deleting the correct file and, when sure, click Yes. Now restart Windows.

Hopefully, this will fix the problem of mismatched icons. If not, then the chances are that your user account is corrupt. This will take longer to repair and the exact process will depend on whether (and, if so, how) your computer is networked. We simply don’t have the room in No Problem to detail all the permutations but Microsoft has a full guide at its website - you will find it by clicking here.