Show hidden files and folders not working

Method 1:

Go to registry editor by running regedit in the run box.
Go to this key:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced

In the right hand area, double click hidden and change the value to 1.
Now you’re all set to go.
Method 2:
Go to registry editor by running regedit in the run box.

Go to this key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden\SHOWALL
Delete the value CheckedValue.
Create a new key called “CheckedValue” as a DWORD (hexadecimal) with a value of 1.
Method 3:
Click Start –> Run –> regsvr32 /i browseui.dll –> enter
A confirmation message will appear like given below
Click Start –> Run –> regsvr32 /i shell32.dll
Wait for the confirmation and click OK.
Method 4:
To fix the above setting, download foldersettings.reg (http://www.4shared.com/file/157256236/2f50d786/foldersettings.html)
and save to Desktop. Right-click on the file and choose Merge. This fix can be applied in Windows XP as well as in Windows Vista systems.