Sometimes you want to share your C: drive in windows 7 for special purpose,and you will find you can not access C drive share from network.You need to change your Remote User Account Control (UAC) to enable Administrative shares in windows 7 with the following steps.
1.Click Start, type regedit in the Start Search box, and then press Enter
2.Browse to the following registry subkey:
3.Right-click key system and and then click DWORD (32-bit) Value
4.Type LocalAccountTokenFilterPolicy for the name of the DWORD, and then press ENTER.
5.Double click LocalAccountTokenFilterPolicy and set it’s value to “1”
6.Done and test if you can share your C drive now.