Hey. I've had this bug, too. It's quite impressive... They'll just stand there and even if you dismiss them or LOG OUT they'll stick around. Amazing.
So the only way I've found to deal with it is to sidekick... They'll all die and you can summon new pets (which won't have the same issue). Just do that whenever it happens... If you can't find anyone lower though you're screwed. Hopefully they fix it!
As I understand it there's a /releaseall command that fixes the problem. It actually kills the pets instead of just making them despawn. That gives you a clean slate to resummon instead of having the dismissal get caught in whatever loop is preventing it from working.
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) Yeah... I had this happen again today. /release_pets gets rid of them. Phew.
This has happened to me a few times over the past few months, not just post-i18. Going into a mission door will also fix them. (But sometimes, going into an outdoor mission would be what messes them up - in which case I'd just leave the mission and re-enter).
Nice to know about /release_pets, though.
I have had this problem as well.
I did not notice it prior to issue 18 GR though.
Outdoor maps makes it happen the most. But have had it coming through train station enroute to a mission. The bots stay there...going into the mission - they show up fine.
On a slightly different note...I had stopped playing my Bots/FF MM because I couldnt stay in Follow/defensive...if I didnt get hit - they would just stand there.
Now it seems they attack...even if I don't get hit...just shot at.
Previously I had played more like a blaster with support...now I'm playing more tanker by opening up with attacks...letting the baddies shoot at me..
My Bots do MUCH better and I dont have to resummon or hardly even repair them now.
In fact got rid of all my heals...and picked up the Hero side epics...Fire 
Oh man oh man am I having fun.
I do HATE HATE HATE when they run into melee though...but can live with that.
I heard rummors that this was broken because of Demons...no proof.
They did fix the hero cold epic issue for MM's in one of the patches since GR released...so we are not forgotten
Edit: How about an Option to "stay at range" Delete melee attack all together or something....
LvL 50 Dark Dark, Emp/Rad Defenders
LvL 50 Inv/Axe, Fire/Fire, Stone/Stone, Mace/Shield Tanks, EM/Inv
LvL 50 Spines/DA Scrapper
LvL 50 Ice/Storm, Ice/Rad, Earth/Rad, 2 Fire/Kin, Ill/Rad, Grav/FF, Controller Elec/Storm
LvL 50 Bots/FF, Merc/Traps, MM Thugs/Traps, Demon/Thermal
Maybe they just thought you weren't tough enough and quit on you.
I can only imagine they really do know about the issue. I pretty much think many or at least enough people posted a bug report on it. One week alone I was a bit annoyed with it and posted a report 4 or 5 times during the week about it. I have been off my Masterminds a bit, hopefully they will one day really tweak the Pet command and AI to allow players a bit more ability to generate commands that mean something to them. I do not feel that all the pets can have the same commands, since the pets are so different.
1. Why Soft Cap is Important : http://dechskaison.blogspot.com/2011...important.html
2. Limits: http://paragonwiki.com/wiki/Limits
3. Attack Mechanics: http://wiki.cohtitan.com/wiki/Attack_Mechanics
4. Rule of Five: http://wiki.cohtitan.com/wiki/Rule_o...e_Law_of_Fives
Wow, just wow.
So I go into Imperial City from Nova and I notice my thugs are hanging out at train station entrance and not following me. I go to the auction house and when I come out same thing. Follow doesn't work, GOTO doesn't work.
So I dismiss them. Now they won't summon.
MM's have been so screwed up this issue I am to the point where I just won't play them. first they screw up pet ai so they run into melee for everything and I say "Okay, I can work around it. " Then they screw up missile swarm for bots and I say "well, I'll stop playing my bot MM until they fix it", which they WON'T.
Now they've totally f'ed pets up completely to where I have to either go into a mission to get them back, or log out.
And none of this is in the fraking patch notes.
Hey devs, way to break a whole AT and show you just don't give a crap.
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