'System is unable to browse the SharePoint server' error after installing the SharePoint Plugin license. (4038244)

'System is unable to browse the SharePoint server' error after installing the SharePoint Plugin license.

NetVault Backup environment details:

NetVault Server: 9.2 Windows 2003 R2 64Bit 16GB Physical
NetVault Client: 9.1.1 Windows 2008 R2 64Bit
SharePoint Plugin: 1.3.1
SharePoint Server: 2010. IIS on one Server and Database on a separate SQL Server 2008 (not clustered). Small Farm Setup as per the guide.

After installing the SQL Plugin license key successfully; browsing the SharePoint Plugin results in an error saying that the system is unable to browse the SharePoint server.

Checked/amended all the below items and still results in the same error message:

1. Disable UAC on the SharePoint Server (and must reboot) to be able to browse using a Domain user account with administrators rights in the plug-in configuration.
2. Add the Domain user account as a Farm Administrator in the SharePoint 2010 Central Administration.
3. Add the Domain user account as a member of the local Administrators Group on the SharePoint Server.
4. Add the Domain user account as a Login on the SQL Server with Server Roles 'dbcreator' and 'securityadmin'.

Further information is in the SharePoint Plugin Users Guide on the following link:

https://support.quest.com/netvault-backup/technical-documents