TYPO3 Core

It seems that I have managed to resolve the error. Since the Typo3 installation was working once before with the same PHP environment etc and the clue that it was symlink related, I continued troubleshooting and by deleting all 3 symlinks and recreating them using the /D flag, the backend was once again accessible.

In command prompt, I entered the following. First we move to the root of the site and then create the relative symlinks:

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C:\Users\Administrator>cd \inetpub\wwwroot

C:\inetpub\wwwroot>

C:\inetpub\wwwroot>mklink /D typo3_src typo3_src-4.3.1

symbolic link created for typo3_src <<===>> typo3_src-4.3.1

C:\inetpub\wwwroot>mklink /D typo3 typo3_src\typo3

symbolic link created for typo3 <<===>> typo3_src\typo3

C:\inetpub\wwwroot>mklink /D t3lib typo3_src\t3lib

symbolic link created for t3lib <<===>> typo3_src\t3lib

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I have tried deleting and recreating the symlinks before, without success, so I am assuming that the reason it worked this time, is because I used the relative paths instead of absolute target paths and also using the /D flag (for directory symbolic link) instead of /J (junction). I think when upgrading Typo3 again, the same issue might occur, because previously I used to only delete the typo3_src symlink and recreate it pointing to the latest source files, but maybe that corrupts something and it is better to delete and recreate all 3 symlinks in future.

Hope this clarifies for anyone else in a similar situation.

Resolved, no change required.

Thanks for the solution Junaid.