Error 1606: Could Not Access Network Location %APPDATA%\

I was installing Symantec Antivirus on one of the client machines today when it prompted me the error (noticed on Windows Vista). I then Bing'd it to find out that this issue appears when the Shell folder of the logged on user has incorrect entries.
It might be the case with any installation and not just Symantec. I recommend you to backup the registry before trying this out.
These are the steps to fix it:

1. Click Start > Run > regedit.exe
2. Locate the registry key: HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders\
3. Delete the entry which shows the error message

Registry editing has been disabled by your administrator

2 methods to enable registry editing. Choice is yours or you might be forced.

1st Method

1. Click Start > Run and type gpedit.msc
2. Navigate to User Configuration > Administrative Templates > System
3. Double click Prevent access to registry editing tools
4. If it's Not Configured then Enable it and Disable it. If already Enabled then just Disable it.
5. Now try regedit.exe

2nd Method

1. Click Start > Run and type in
   REG add HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System /v DisableRegistryTools /t REG_DWORD /d 0 /f
2. Now try regedit.exe

Note: You might have to restart the computer for changes to take effect.