How to delete iMessage archive

Question

Hello,
I have used Messages on a work machine and it has synced all of my iMessage history from my iPhone (as it should have, and as I wanted). It's time for me to return this machine, and I'm trying to erase all of my chat history (the system user account either cannot or is not being deleted).
I have removed:
~/Library/Containers/com.apple.iChat
~/Library/Messages
~/Library/Preferences/com.apple.iChat.*
~/Library/Preferences/com.apple.iMessage.*
Yet when I open Messages, the chat histories all remain. The iMessages account has been removed, so it's not re-syncing. Where are these messages being stored?
Thanks,
Tim

Answer 1

Hi,
iMessages "History" - the bit that refills a chat with old info when you reconnect to someone - is held in chat.db items in ~/Library/Messages.
IF you also set it up to Save on Close it will also save all Chats from iMessages as well as other Accounts (AIM, Jabber, Bonjour, Yahoo) in the Archive folder.
This is in ~/Library/Containers/com.apple.iChat/Data/Library/Messages.
You seem to be saying you deleted the containing folders so the info should have gone.
The .plists for iChat that have extra bits in them refer to the Account types (AIM, Jabber, Yahoo and Subnet for Bonjour) the Recent List (LSShared) and the Status Messages for the Buddy Lists (*er StatusMessages)
You will also need the com.apple.imagent.plist (this holds all the account info for accounts that Login.
The iMessages account details are held in com.apple.ids.service.com.apple.madrid.plist
I would also delete anything that listed IDS as they also show the Apple ID and any iPhone Number
There are now many of them if you set up Text Forwarding for SMS as well.
I would also delete all the IDS items listed in the KeychainAccess App.
Also in ~/Library/Containers/com.apple.soagent/Data/Library/Preferences delete the Contents.
This holds mainly Alias items to the .plists in ~/Library/Preferences but some are actual .plists and relate to Messages.
I would tend to clear all conversations of the individual iMessages (or other messages) then delete the conversations before removing the Apple ID from the Messages > Preferences > Accounts > Sign Out button and remove the madrid item once the app has been closed.
I have seen one other post where someone said the Messages main window continued to show Chats after the Archive and Chat.db items had been removed.
I wasn't sure they had removed chats from the main window at any stage. If they are not removed and seem to persist there must be a different mechanism to re-populate the window which I am not sure where it would be.
8:46 pm      Wednesday; February 11, 2015
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