Hi,
The "fix" that used to work in iChat (any verison) and Messages 7.x.x does not seem to work in Messages 8 in Mavericks. (deleting the com.apple.ichat.plist)
Has the .plist been recreated ?
Messages 8 is subject to the Sandboxing features of Mavericks.
This means that the app Reads and Writes to the .plists via a different route than you just looking at them in ~/Library/Preferences.
The com.apple.ichat.plist should be Written (recreated as you start up the app) as it needs to hold the bandwidth (Internet Speed portion the computer has and the app has compared with other activity).
In a Finder window use the View Menu > Show Path Bar.
Now use the Go Menu whilst holding down the ALT key and Select the Library that appears.
Now navigate to Containers/com.apple.ichat.Data/Library/Preferences
Most of the items here are Aliases back to the ~/Library/Preferences items directly.
Right Click the Preferences folder in the Path bar and Select the Get Info option
At the bottom of the Info Panel check your are the owner and have Read and Write Permissions.
Your Shortname should be in the list with the (Me) part and you should have Read and Write Permissions
Using the cogwheel type icon you should see the greyed out message if you already Own the folder
Repeat the check moving through the folders to the left in the Path Bar (Library, Data, com.apple.ichat, Containers and in fact the actual ~/Library itself)
You should have Read and Write permissions all the way through.
It is late where I am and it will be a while before I pick up on any replies.
10:02 pm Thursday; March 27, 2014
iMac 2.5Ghz i5 2011 (Mavericks 10.9)
G4/1GhzDual MDD (Leopard 10.5.8)
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Mac OS X (10.6.8),
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