What software is used to read the current access rights map (AD to files on the local file server and reassign them in bulk?

Question

Active Directory

Given: local area network for 40 machines. Windows 2012 with AD is installed on the local file server. Users from local machines exercise their access according to the established rights, but over the years, access rights have become a mess, because. the remote sys.admin did not keep statistics of new users / dismissed, as well as personnel reshuffles.
The task and requirements for the software: it is required to put things in order, namely, on the one hand, remove unused accounts, and on the other hand, reassign file access rights based on user groups. Requires free / open source software to draw up a current picture of file permissions, as well as for mass reassignment of these rights.

Answer 1

1) You first need to put the AD structure in order, namely, disable all unused accounts, do not delete them! (Human Resources Department to help you)
2) Tidy up file storage, create its structure by departments, for example. (agree with the heads of departments who should have full access, who should only read)
3) Create access groups in AD and assign rights to folders through these access groups.
4) Remove from folders all accounts that are assigned directly (not through access groups)