Trying to view database properties and getting a cannot impersonate `guest` error

One of my DBAs is trying to look at the database properties of a database by right clicking and selecting properties and is getting the following error: > Cannot show requested dialog. (SqlMgmt) > > An exception occurred while executing a Transact-SQL statement or batch. (Microsoft.SqlServer.ConnectionInfo) > > Cannot execute as the database principal because the principal "guest" does not exist, this type of principal cannot be impersonated, or you do not have permission. (Microsoft SQL Server, Error: 15517) Points of interest: - The guest account has been disabled (no connect permission) - The DBA is a member of db_owner on the database, but not sysadmin on the instance. - He has this permission through a role, but does not have a user directly in the instance let alone the database. - This is a windows authenticated login. - I tried creating a SQL Id and testing but couldn't replicate. - The version of the instance is SQL Server 2016 (SP1) - 13.0.4001.0 (X64) - On Windows Server 2012 R2 Standard 6.3 What I don't understand is why he would be impersonating anything since he is a member of db_owner, particularly when trying to open the properties dialog. I've checked here: https://dba.stackexchange.com/questions/134026/cannot-execute-as-the-database-principal-because-the-principal-guest-does-not but the service account running the named account has sysadmin access so this shouldn't be a problem.