Error below is seen when creating a new custom report, site to site report, or analysis report.
Microsoft pushed Windows Updates that lock down ASP.NET in IIS.
NFA and ReporterAnalyzer - all versions.
1. Windows Server 2008: Right click on Computer, click Manage, expand Configuration, expand Local Users and Groups.
Windows Server 2012: Hit the start button and search for "Edit Local Users and Groups."
2. Select groups, then double click the "Administrators" group.
3. Click Add.
4. Change the Location to the local server and not the domain.
5. Then enter "IUSR" and click "Check Names" then OK.
6. Then right click on the \CA\NFA or \Netqos\ directory and select properties.
7. Select the Security tab, and add the IUSR account and give it full permissions.
8. Do the same exact thing for the IIS_IUSRS account with full permissions.
9. Open a command prompt as an administrator and run "IISRESET".
10. Log back into NFA and see if you can create a new custom report.