[TYPO3-windows] Typo3 Backend 500 Server Error After UpgradingtoT3 4.3.1 on Windows 2008 IIS7 (Pim Broens - Redkiwi)

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>
> Next line of troubleshooting, I would say to check all error_logs of
> course.
>
> Might it be possible to use a physical source instead of symlinks? At
> least for testing purpose?
>
> Kind regards,
> Pim
>
>
Thanks for your continued assistance Pim.  I checked the PHP error logs and
it reported this error for attempts to login to the admin backend:

#####
PHP Fatal error:  Cannot redeclare class backend_toolbarItem in
c:\inetpub\wwwroot\typo3_src-4.3.1\typo3\interfaces\interface.backend_toolbaritem.php
on line 36
#####