Follow up to this Q&A.
According to one of the answers it should be possible to solve a MD5 digest mismatch by synchronizing username, password and domain between VTP Client and Server and subsequently executing a VLAN change on the VTP Server to align the MD5 digest on the Client.
However, after executing these steps and executing
sh vtp st on both the VTP Server and the Client a discrepancy between MD5 digest between these two remains, which avoids that the VLAN database on the VTP Client is synchronized with the one of the VTP Server.
Once a name of a VLAN has been changed on the VTP server the MD5 digest will be changed. However, the MD5 digest on the client remains the same and the following message is shown:
*** MD5 digest checksum mismatch on trunk: Po1 ***