The Great Escape Zone Event
I had this same issue last night. Started the zone event, killed 30 Praetorian PD, and when I zoned into the building all my powers were suppressed. Failure resulted.
I wonder if it has to do with the inspiration nerf-on-zoning meant for AE, or the re-activated Studio B suppression that both happened with the last patch. Hmm

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Beta Patch Notes says this is fixed on Beta, so, the fix should be coming to Live, soon.
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I just got done trying this zone event and had the same issue. Outside my powers were working, but as soon as I went in the door, they were all suppressed (except for walk and a few others). Thankfully I was able to summon all my pets outside and finish it with them... so I basically spent the rest of the event just leading them around, hoping they'd be enough.
I went to do this Zone event because i needed the Failed Experiments for a badge... Started off all nice and normal. When in the door after killing the first 30 Ghouls and all my powers/inspires suppressed. Event failed because I couldn't kill the second set of 30.
Anyone else run into this issue?