Taxcycle appears to pull the login credentials from the information used to logon to your computer. If you have a NAS that does not use those credentials, rather credentials that are stored in the Windows Vault (such as is the case when you don’t use Active User Directory), you can’t use the Client Manager to index files stored on said NAS.
Attempting to index directories results in “insufficient user permissions” when attempting to do so. I suggest having Taxcycle poll the Windows Vault for credentials that would be used in these cases.
By default, the Client Manager server runs under the local computers System account. The System account can access all of the resources and shares on the local computer, but it can’t access resources elsewhere. This is the cause of the “insufficient user permissions” error.
You can change the user account the Client Manager server uses to another user account that does have the necessary permissions to access external resources (such as a NAS).
I should also note that if you change the Client Manager user account, you’ll need to use auto-update to update TaxCycle. The full TaxCycleSetup.exe install will reset the user account back to System.