There can be 3 possible causes for this error:
The Asset Manager licence has expired
Please check that a valid license for Asset Manager exists and is applied to the application. For this, please review the latest licence renewal email that would have been sent by our Despatch team and compare the Asset Manager unlock key against the unlock key that is presented by Asset Manager when logging in.
The user has not updated the licence
Please check if this user has the latest licence applied to their installation. If not, apply the license using the article referred to above.
The user may not exist within the database
The user may not exist within the database and therefore would need to be created.
Note: The Asset Manager user list does not automatically mirror the Dimensions user list.
For this, someone with the authority to use the SA or the Hosting.Admin (for Access Hosted) user account should log into Asset Manager in order to create the user which does not exist in the Asset Manager database.