Most likely you are unzipping these "m" type updates into a folder your workstation is not running AA from. Help/About Active Accounting reports the version number it finds from the drive and folder your workstation is currently pointed to. Exactly where your workstation is pointing to, to find the AA program files is found on the line that reads: "Application Path". This path is where you should be unzipping the "m" update too. Typically it is the one and only Active Accounting folder on your server.
There is really only one other possibility and that is that the update is not successfully unzipping. There would be some error message indicating that it was not successfully finished unzipping however. The most likely cause for not unzipping is someone still in Active Accounting or in some cases the operating system only "thinks" Active Accounting is still 'in use' or 'open' and really is not. In the first case the user should log off. In the latter case what you can try is to power your workstations down in an orderly fashion (close all programs 1st) and if just doing that doesn't help, do the same to the server and then after restarting the server, start just the one workstation you are using and try to unzip again. If this doesn’t work try downloading the update again from the web site. It may have been a bad download and this may be the cause for not being able to unzip itself.