Blocking a user means you will no longer receive any messages from that user in the Messenger.
The blocking will be "silent", meaning the blocked user will not be notified that he/she has been blocked by you,
and the blocked user can therefore still write you messages as usual, but you will not see those messages or be notified about them,
as long as you have that user blocked.
i installed the excel add in, however it seems not work. My excel is office 365. just wondering how to enable this plug in, or how to download the plug in again to reinsatall. Alex