Grant Purview Export Permission

When exporting the results of a Microsoft Purview Content Search, the user must have the permission. This permission cannot be granted by the same user to which it is being granted.

First, Connect to the Security and Compliance Powershell

Connect-IPPSSession

Add eDiscovery Manager Role to admin:

Add-RoleGroupMember "eDiscovery Manager" -Member <username>

Promote useradmin to Case Admin

Add-eDiscoveryCaseAdmin -User <username>

Microsoft Answers: user-with-global-administrator-and-compliance-admi