I backed up SQL, made a copy of the program files directory.
Downloaded the setup.exe from the link in the email.
Ran the install, it succedded.
rebooted the server, since we had a downtime scheduled anyway.
It is scanning, the website comes up but all default reports which show under
 Dashboard 
 Software 
 Hardware 
 Server 
 General 
 Active directory 
 Devices 
are either in duplicate or triplicate. All reports I have added over time to those pages still only show up once.
The links to the reports appear to be identical:
http://myserver.domain/lansweeper32/default.aspx?item=cust&det=web40repdeviceoid&title=Device%3a+Unique+SNMP+OID
http://myserver.domain/lansweeper32/default.aspx?item=cust&det=web40repdeviceoid&title=Device%3a+Unique+SNMP+OID
Did I miss something in the patching process?