An Access Control List (ACL), with respect to a computer file system, is a list of permissions attached to an object. An ACL specifies which users or system processes are granted access to objects, as well as what operations are allowed on given objects.
Each entry in a typical ACL specifies a subject and an operation. Sometimes, your ACLs can become corrupted for one reason or another. Since these are tied into your registry on Windows based systems, system instability and crashes may result.
Important services may fail to launch as well at startup. One particular service is the Windows Event Log, which is responsible for maintaining records of all activity on your PC in the event of an error. These logs are accessible through the Event Viewer, which can be opened through the search dialog on your start menu. Not having access to these logs may make it difficult and more time consuming to correct problems with your PC.
If you are facing such issues, you may want to try Access Control List Repair Utility for Windows 7 & Windows Vista.
Access Control List
To run this repair utility, please follow these instructions.
1. Create a system restore point first.
2. Download the Access Control List Repair Utility from this page.
3. Double click on the subinacl.msi file provided with the download. If it does not work for some reason, you can find the download from Microsoft. The SubInACL tool in Windows helps you in resolving setup or update errors.
3. Right click on the reset.cmd file and Run it as Administrator. This Operation can take anywhere from several minutes to half an hour or more, depending on the speed of your system.
4. Run the enclosed command.cmd file as administrator.
5. Restart your Windows computer.
This will reset your ACL’s.
If you do not like the results, you can always restore your PC back to the created restore point!
The Commands used in this utility have been taken from this MSDN Forum thread.