Just got a response to my ticket with an apology for the inconvenience and they are looking into this issue. It sounds like they’re still working out the specifics of what caused it and don’t yet have a resolution. Basically told to keep up with forum blue posts for more info.
This is a real bummer with TWW launch so close on the horizon.
They have done the opposite of fix the problem. Now even tabs that were only missing a little bit are missing HEAPS or all of the stuff. They are making it worse rather than better. This is really terrible.
Blizzard, please fix this, as you are preventing people from being able to digitally hoard their stuff, and for some of us, that is a core part of our fun (and yeah to all those who are gonna complain that it’s sad, I don’t really care what you think, control over my stuff is fun).
Also, it’s a pretty jerk move for blizzard to have not bothered to properly test changes before implementing them and therefore doing this.
I too am experiencing this issue for Entropy guild on Feathermoon server. All seven guild bank tabs are missing a vast number of items. I also have an issue in that my alts are unable to withdraw gold from the guild bank based on the 30K daily limit I have set. Say I want to withdraw 5K on an alt, I cannot. I might be able to withdraw 1K, but when I try it a second time it won’t allow me to. No error message or anything. I know you guys have backups so I would like my guild bank restored prior to this issue happening. All the time and energy I have spent storing mats for leveling professions make this a BIG DEAL. Your time and attention to these matters is appreciated.
Same here. All 7 tabs are missing. just a storage bank. but ugg ya!
Also have guild bank items missing. Entire stacks of things just gone. Not in every tab, but some tabs missing up to eight items, others only two. It seems pretty random, but since I am picking about making full stacks, it’s noticeable. No withdraw in the logs, so it’s really frustrating.
Add your issues to the main thread in bug reports.
I had a reply to my ticket from the day this started. it had a link to a support article…
They are looking into this, but what, if anything, can be done remains to be seen.
Also just noticed this issue today, I share a guild bank with my wife, all 8 tabs are completely empty, no logs. Have not checked all the guild banks we share yet. Tried resetting the UI which was suggested but no luck
Many Items from my personal guild is missing and I checked where not withdrawn from my guild bank what is going on i had alot of mats in this guild
Ever since this bug appeared I check my guild bank. As of tonight, it’s almost totally emptied out. I’ve been taking screenshots of the disappearing items and the logs and I suggest others do the same.
Same issue for our Guild Bank on Moon Guard: Items simply VANISHED. We lost ore, Grand Feasts, Repair Anvils, all the stuff we pack for Raiding. Posting here as my Support Ticket asked me to do so.
Elders Of the Sacred Age Guild, Tichondrius Realm massive bank deletion … If this is the new game design teams true show of talent … Combined with the constant sales of GROUP Dungeon runs, in game player commercialism .The Game just isn’t what it used to be … I’m just glad I have not bought into TWW , and my subscription ends shortly , so … Best of Luck to the devs …
are they working on this problem to restore missing items to our guild banks?
As of this morning, our horde guild bank on Aerie Peak (which was nearly full) has now about 35 to 40 items left in it, logs have all consistently read 5 months or more as last entry and no one claims to have noticed it happening.
The alliance bank on same server also had about 1/2 of the items removed unexplainably with logs stating same time frame. What about all this expense and gathering time blizzard?
“Developers” are “working,” whatever that means.
No one is communicating, though, other than “we have no root cause” “we have no time frame” “we have no workaround” “we have no resolution” etc etc so clearly the matter is well in hand
I have an “alt” bank where I would store all of my old materials. It was 6 tabs of nearly full of materials (probably worth a lot on the Auction House) and nearly all of it is missing. Only like 1-3 items are there per page.
This is incredibly alarming!
Same here. Tens of thousands of mats now gone.
Same for me. Thought I’d been hacked. Logs can’t be trusted. I’ve deposited and withdrawn several items today, but the logs say it’s been 9 days since any activity.
p.s. The War Within launches Aug 26th. 
I have been checking my infected guild bank every day to see if blizzard fixed anything but nothing as of yet will blizzard replace our lost mats, they took my most expensive items like rousing and awakened motes
Right! all tabs missing in my GB, this should have been a priority fix
Just noticed this a few days ago for my personal guild. No log of anything withdrawn, but tabs that were full have missing items – seems almost random. Since those tabs had trade supplies for professions for each expansion, I thought perhaps they may have nuked a bunch of old trade supplies. Alas, that isn’t the case it appears. Was so hopeing Blizzard might thin out the old trade supplies (consolidate the cloth from classic? etc.).
More things seem to continue to disappear since I first noticed this, but not sure exactly.