Sorry for bothering you again. However, the fact that it works for me on two differenc computers and brakes Mail app for you intrigued me.
the file Accounts.plist contains separate parts for each account you have configured on Mail app.
The one that I have configured for my domain that I host at Google looks like one bellow. I only changed personal information - it is in upercase letters and bold in this example as well as changed uniqueId (the last string part at the bottom). Some other parts you may have different as well as these describe how long to keep Trash, Junk etc.
<dict>
<key>AccountName</key>
<string>SOME DOMAIN</string>
<key>AccountPath</key>
<string>~/Library/Mail/V2/IMAP-NAME.SURNAME@mail.SOMEDOMAIN.com</string>
<key>AccountType</key>
<string>IMAPAccount</string>
<key>ArchiveMailboxName</key>
<string>Archive</string>
<key>AutoFetch</key>
<string>NO</string>
<key>CompactWhenClosingMailboxes</key>
<string>YES</string>
<key>ConfigureDynamically</key>
<false/>
<key>DateOfLastDraftCleanup</key>
<date>2011-05-08T03:24:33Z</date>
<key>DateOfLastSync</key>
<date>2012-12-09T00:07:46Z</date>
<key>DaysBetweenSyncs</key>
<integer>2</integer>
<key>DraftsMailboxName</key>
<string>Drafts</string>
<key>EmailAddresses</key>
<array>
<string>NAME.SURNAME@SOMEDOMAIN.com</string>
<string>SUPPORT@SOMEDOMAIN.com</string>
<string>SALES@SOMEDOMAIN.com</string>
<string>INFO@SOMEDOMAIN.com</string>
</array>
<key>EmailAliases</key>
<array>
<dict>
<key>alias</key>
<string>SUPPORT@SOMEDOMAIN.com</string>
<key>name</key>
<string>SUPPORT</string>
</dict>
<dict>
<key>alias</key>
<string>SALES@SOMEDOMAIN.com</string>
<key>name</key>
<string>SALES</string>
</dict>
<dict>
<key>alias</key>
<string>INFO@SOMEDOMAIN.com</string>
<key>name</key>
<string>INFO</string>
</dict>
</array>
<key>FullUserName</key>
<string>YOUR REAL NAME</string>
<key>GmailCapabilitiesSupport</key>
<integer>2</integer>
<key>Hostname</key>
<string>imap.gmail.com</string>
<key>IsSyncable</key>
<true/>
<key>JunkMailboxName</key>
<string>[Gmail]/Spam</string>
<key>NotesMailboxName</key>
<string>Notes</string>
<key>NumberOfDaysToKeepJunk</key>
<string>1</string>
<key>NumberOfDaysToKeepSentMessages</key>
<string>-1</string>
<key>NumberOfDaysToKeepTrash</key>
<string>1</string>
<key>PortNumber</key>
<string>993</string>
<key>PreventDismemberment</key>
<string>NO</string>
<key>QueriedUserForPrefix</key>
<string>YES</string>
<key>SMTPIdentifier</key>
<string>smtp.gmail.com:NAME.SURNAME@SOMEDOMAIN.com</string>
<key>SSLEnabled</key>
<string>YES</string>
<key>SecurityLayerType</key>
<integer>3</integer>
<key>SentMessagesMailboxName</key>
<string>[Gmail]/Sent Mail</string>
<key>ServerID</key>
<dict>
<key>name</key>
<string>GImap</string>
<key>vendor</key>
<string>Google, Inc.</string>
</dict>
<key>StoreDraftsOnServer</key>
<string>NO</string>
<key>StoreJunkOnServer</key>
<string>YES</string>
<key>StoreSentMessagesOnServer</key>
<string>YES</string>
<key>ToDosMailboxName</key>
<string>Apple Mail To Do</string>
<key>TrashMailboxName</key>
<string>[Gmail]/Trash</string>
<key>Username</key>
<string>NAME.SURNAME@SOMEDOMAIN.com</string>
<key>uniqueId</key>
<string>111111-22222-333334-44444</string>
</dict>