When you are installing Veeam search server according to Veeam Backup & replication 5.0 page 41 it says use a administrator account. When you are preparing for file browsing and advanced searching (page 165) you will add the search server to the Veeam Back-up Enterprise Manager. You can get this error while going trough the wizard.
The problem is that the account doesn’t have enough rights. I went in the configuration of Search server and changed the Standard account for access to the account that is used to run the Veeam search service. ( Sorry picture is in Dutch)
this solved my problem during the add Search server wizard.
Was once an enthusiastic PepperByte employee but is now working elsewhere. His blogs are still valuable to us and we hope to you too.