Subversion Exception!

I've searched the archives and this has been reported back as far as 1.7.3 that I could see. I couldn't see that it was reported against 1.7.6 yet. I deleted my entire tree below the root and got the same error again. Just doing an update on Windows 7 64 bit OS. The repository is approximately 8.1 GB.

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Subversion Exception!
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Subversion encountered a serious problem.
Please take the time to report this on the Subversion mailing list
with as much information as possible about what
you were trying to do.
But please first search the mailing list archives for the error message
to avoid reporting the same problem repeatedly.
You can find the mailing list archives at
http://subversion.apache.org/mailing-lists.html
Subversion reported the following
(you can copy the content of this dialog
to the clipboard using Ctrl-C):
In file
'D:\Development\SVN\Releases\TortoiseSVN-1.7.6\ext\subversion\subversion\libsvn_wc\update_editor.c'
line 1583: assertion failed (action == svn_wc_conflict_action_edit || action
== svn_wc_conflict_action_delete || action == svn_wc_conflict_action_replace)
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OK
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