When you click on the Pictures, Music or the Documents link the Start menu, nothing may happen. Also, when you right-click on one of the links and choose Properties, the Location tab may be missing.
This happens if the corresponding shell folder was relocated earlier and is pointing to an invalid location. For instance, if an user relocates the Documents folder to a removable hard drive and then disconnects the removable hard drive at a later stage, this problem is seen. If you wish to reset the shell folder paths to the default location, use the following steps:
HKEY_CURRENT_USER \ Software \ Microsoft \ Windows \ CurrentVersion \ Explorer \ User Shell Folders
For example, to reset the Documents folder path, double-click Personal and set its data to %USERPROFILE%\Documents
Importantly, make sure that the Value type is REG_EXPAND_SZ, as we're using an expandable string (%userprofile%) in the Value data. If the value is already set as REG_SZ, delete it and create a new value of the correct type.
NOTE: The default value data for various shell folders are listed in article How to move the special folders in Windows Vista (See Method 2 in the linked page.)