Soo we have a seperate account for our guild bank, holding MC / ZG / AQ / Naxx mats, aswell as a plethora of potions and consumables etc aswell as almost 25k gold.
Its owned by one of our officers and about 6 officers have access to it in total.

Today we just found out it has been banned, and the reason being:

Im assuming other people have the same situation with guild banks and shared access, but the huge loss of quest turnin materials for armour, the mass of resistance potions and flasks to help ease the learning costs for the guild in naxx... its just shattering to comprehend the time/effort that is lost now and the huge setback on gearing ourselves up.

Anyone experienced this type of situation, is it avoidable? has anyone had it happen and then got it renounced nd returned?

What exactly did someone do to get the account banned?

We use multiple banks to handle the different functions (gold/ah, cores/idols/scarabs/scraps, potions/herbs). This helps with such issues. Also, it helps limit the need of account sharing.

As for fixing your issue, I agree with having your guild members send in a ticket on it and just don't mention the sharing of the account.

Aparently they think we are a gold farmer account (?)

We've done nothing recently, we have income from enchants/crafting which never exceedes about like a few hundred every few days, and generally splurge on some herbs and elementals every few days.
And ofcourse we mail in some coins/scarabs/idols/scraps after raids... =/

Yeah, making it a separate account is a dicey proposition. I'd recommend you call Blizzard and try to get a rep on the phone -- their phone support is worlds better than playing GM roulette and hoping you get lucky. From their perspective, if you have an account that serves solely as a clearing house for tens of thousands of gold and hundreds of consumables and other materials, that's going to set off all sorts of red flags.

This is a big part of the reason I keep the guild bank on my own account and no one other than me has access to it.

Not say anything about you nor your guild, but don't be surprised if it turns up someone is siphoning resources.

I agree with the above posters, however. Call up Blizzard. If I ever needed anything done with my account, I'd use the phone, not the petition system.

"Involvement in online trading" means that one of your beloved officers did something really stupid. I know that none of your officers would ever do something so unscrupulous, and it's never happened before in an online game! But someone on that account is either:

a) buying gold on the interweb
b) selling gold or items for real world currency

The GMs are smart enough to not ban a guild bank, (even though they could if you had multiple people accessing it) but you really shouldn't be having multiple people logging in to an account. You're just inviting drama by leaving an account with thousands of dollars worth of items wide-open for multiple people to scam, leaving you scratching your head trying to figure out which one actually got the account banned. They don't just ban people for having a ton of gold and items. Someone did something dumb.

we've watched our gbank go up to the state its at today its never lost any gold without herbs and stuff in its place, and even then not at huge amounts like thousdands per time.

Theres no real way we can see that one of us could of sold/brought stuff without any of the others knowing or noticing

no most Gms at blizzard are retards. This can very easily happen if your a large guild with a big economy server. OMG.. he sent has a a billion gold and sends out 5000 potions a week !! BAN HIM BAN HIM !

like they suggested, call blizzard and explain the situation. If your lucky and don't pull a mouth breather, then they should unban you.

I would be highly surprised if these bans are based on anything other than some sort of query on the DB which flags up suspicious activity. All they would do is run a query that checks for a series of suspicious things like:
- Large daily throughput of AH transactions.
- more than xxxx gold on an account
- Large daily through put of gold and items.
- Accounts used for 20+ hours a day (or even from multiple static IP's)

They might have an employee run over the basic details of each case before implementing the ban, but it wouldn't surprise me if they accidentally banned a few legitimate accounts in the process.

Blizzard seems to have abandoned any notion of presumed innocence when non-domestic IP addresses are involved. We have a chinese player in our guild that got banned this week an evening after placing a stack of arcane crystals on the auction house. He received a form letter with similar wording as the OP.

"Access to this account has been permanently disabled for exploitation of the World of Warcraft economy or for being associated to accounts which have been closed for intended exploitation."

This is character in T3 being banned for being a gold farmer...

A handful of emails from our guild and the account got restored and the suspension history cleared. Pretty much it looks like they aggressively went after anyone logging in with chinese IPs and presumed guilt on them all. The account was then restored after an afternoons worth of investigation and the ban history cleared. Pretty much the absolute minimum amount of investigation cleared this account, so how was it ever banned in the first place? The whole thing is more than minorly disturbing.

It could be coincidence but if anyone from SE Asia logged into that guildbank I would not be surprised if the same thing happened to you.