I have recently seen that a new update has been pushed to these Mag boxes. If you have your updates set to Auto, then the receiver probably did get an update in last couple of days. The update was said to be another step in implementing exclusively the Munistra software/middleware, while servers using the Stalker software/midddleware may run into some issues.
Shown below are quotes from a guy 'off the street', just one day ago...
'They are not blocking any more ...its just a marketing gimmick to promote their OS Munistra so IPTV provider switch to it'
'Now provider have to update their stalker to meet new software....and if user don't want to face such thing, then simply disable auto update'
end quote
So if your mag receivers took an update recently, it may be wise to first turn Auto Update to OFF and leave it off, then try loading that No_Block file or if you have an older file stored away somewhere for them mags, then load that older file (older by at least a year ago, or so).