To Unhide The Hidden Folders...

I''l give you a registry key to fix this problem.
Open notepad, copy the text (in the box) at the link below in notepad:

http://www.google.co.in/notebook/public/…

Save this file as "filename.reg" where filename is any name you want but make sure the extension is ".reg" and not anything else.
Next, run this file by double-clicking on it & click "Yes" on the message that appears. Finally, restart the PC for the changes to take effect...

Also, be sure to scan the PC with the Antivirus software once the hidden files are visible since your friend's problem is caused by a worm....

If you're confused regarding any part, contact me via email.... :)

Click Start/Run,type regedit then press Ok

Navigate to the following registry key:

HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Explorer\Advan ced\Folder\Hidden\SHOWALL

Now right click on,and delete the value "CheckedValue" in the right hand window.

Now create a new "DWORD Value" called exactly CheckedValue in the right hand window.

Double click on CheckedValue.

In the opening 'Edit DWORD Value' box,set the 'Value data:' to 1

Press Ok,exit regedit,restart your pc.

1. Click “Start” -> “Run…” (or press Windows key + R)

2. Type “regedit” and click “Ok”.

3. Find the key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\

Advanced\Folder\Hidden\SHOWALL

4. Look at the “CheckedValue” key… This should be a DWORD key. If it isn’t, delete the key.

5. Create a new key called “CheckedValue” as a DWORD (hexadecimal) with a value of 1.

6. The “Show hidden files & folders” check box should now work normally. Enjoy!