**IF YOU ARE COMFORTABLE WITH ACCESSING AND EDITING THE REGISTRY**
Check this out - navigate to:
look for a DWORD "restrictanonymous" and see what the value is. If it is anything other than 0 (zero), right click the DWORD, select MODIFY and change the decimal value to 0 (zero).
A word of warning, there is a DWORD "restictanonymoussam" just below the one you want - DO NOT change this.
Close regedit and reboot the computer.