This is a bug that I haven't seen any news on being fixed.
See
https://knowledge.mcafee.com/SupportSite/search.do?cmd=displayKC&docType=kc&externalId=612622&sliceI...which says:
When accessing another computers' VirusScan Enterprise console through a remote console connection, is unable to execute one of the following tasks on the remote computer:
*
On-Demand Scan task
*
Update task.
Attempting to run an On-Demand task on the remote computer via the remote console actually unexpectedly runs the On-Demand scan on the local computer in error.
Attempting to run an AutoUpdate task on the remote computer via the remote console does not run at all and does not have the same unexpected result as the On-Demand scan by running on the local computer.
Using the Update Now option, a connection window pops up and then disappears.