Hi RayMond5.5,
Based on my understanding, you can't find shared folder after you reinstalled OS on you computer.
Do you log on to the win 7 computer as a member of a group that has the appropriate right to read the shared folder?
Where does the shared folder locate on? If the shared folder is the one that located on the local disk C, after you reinstall the operation system, it will disappear.
If the shared folder locates on a remote computer, you may access it by appropriate user account.
Besides, you may open computer management, click shared folders to view all the folders shared in the group.
If you would like to find the better solution, you may post your problem to Windows client forum, here is the link:
https://social.technet.microsoft.com/Forums/windows/en-US/home?category=w7itpro%2Cw8itpro%2Cwindowsvistaitpro%2Cwindowsxpitpro%2Cwindowsintune
Best Regards,
Anne He