Some companies keep tight control on which accounts can be a member of the sysadmin fixed server role in SQL Server. When installing CRM, although the installing user does not need to be a domain admin, the user does need to have certain administrativwe rights and this includes being a member of the sysadmin role on the SQL Server as per this article https://technet.microsoft.com/en-us/library/hh699825.aspx under the section Microsoft Dynamics CRM Server setup.
An on-premise install of Microsoft Dynamics CRM 2015 requires:
- Windows Server 2012 or later
- SQL Server 2012, SQL Server 2012 R2 or SQL 2014
Microsoft Dynamics CRM 2013 with Service Pack 1 (or later) can be upgraded to CRM 2015.
Client: Windows 7 or later
Browsers: IE10, IE11, Chrome, Safari and Firefox
ADFS 2.0, 2.1 2.2 (ADFS 2.0 must be installed on a different server from CRM)
Exchange 2010 or 2013
Outlook 2010 or 2013 (cached Exchange mode)
Windows SharePoint 2010 SP1 and 2013