I had the same issue and found its known when deploying the EV Report in EV 8.0
Hopefully this will help
Dan
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http://seer.entsupport.symantec.com/docs/317967.htm
After Installing and Configuring Enterprise Vault (EV) Reports for version 8.0, cannot access Site Settings - Security (rsaccessdenied)
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Exact Error Message
The permissions granted to user '<Domain>\<Username>' are insufficient for performing this operation (rsAccessDenied)
Details:
The configuration process will setup the Reporting user and deploy the EV Reports.
In EV 8.0, EV Roles-Based Authentication (RBA) is used for EV Reporting and SQL Server Reporting Services (SSRS) RBA is not supported.
The access to settings related to SSRS security and management has been denied as part of the EV Reports functionality.
In order to implement the EV RBA security, the configuration process also makes changes to the rsreportserver.config configuration file for the SRSS instance.
The values under the security value of the config is changed:
Before:
<Security>
<Extension Name="Windows" Type="Microsoft.ReportingServices.Authorization.WindowsAuthorization, Microsoft.ReportingServices.Authorization" />
</Security>
<Authentication>
<Extension Name="Windows" Type="Microsoft.ReportingServices.Authentication.WindowsAuthentication, Microsoft.ReportingServices.Authorization" />
After:
<Security>
<Extension Name="Windows" Type="Symantec.EnterpriseVault.Reports.SecurityExtension.Authorization,EVSecurityExtension" />
</Security>
<Authentication>
<Extension Name="Windows" Type="Symantec.EnterpriseVault.Reports.SecurityExtension.Authentication,EVSecurityExtension" />
This issue results from how RBA has been implemented in Enterprise Vault 8.0. However there are a few workarounds available:
Workaround 1:
This workaround sets the security configuration back to pre-Enterprise Vault 8.0 functionality.
A. Open the rsreportserver.config for the current SSRS instance.
B. Locate and change the following values for the Authorization and Authentication Security Extensions:
1.
<Extension Name="Windows" Type="Symantec.EnterpriseVault.Reports.SecurityExtension.Authorization,EVSecurityExtension" />
Back to:
<Extension Name="Windows" Type="Microsoft.ReportingServices.Authorization.WindowsAuthorization, Microsoft.ReportingServices.Authorization" />
2.
<Extension Name="Windows" Type="Symantec.EnterpriseVault.Reports.SecurityExtension.Authentication,EVSecurityExtension" />
Back to:
<Extension Name="Windows" Type="Microsoft.ReportingServices.Authentication.WindowsAuthentication, Microsoft.ReportingServices.Authorization" />
Note: This workaround will stop the EV RBA integration with SSRS and default EV Reporting to use SSRS RBA.
Workaround 2:
A dedicated Sql Reporting server can be set up for EV reporting.
Workaround 3:
EV reporting can be installed to a named instance of SQL on the Sql Server Reporting Services server.