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I'm using error_log which has been working fine for years under IIS 6. Recently I upgraded to IIS 7.5 (Windows 7) and the messages logged by error_log stop appearing.

In fact nothing is going to the log. If I call an incorrect function to force a real PHP error, it gets reported to the screen, but not to the file. My ini settings:

error_reporting=E_ALL & !E_DEPRECATED

I've also added < httpErrors existingResponse="PassThrough" /> to the web.config file in my virtual directory but it doesn't work even after a restart.

Can anyone shed any light?

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up vote 2 down vote accepted

The problem eventually turned out to be access permissions for the folder where the error log was. I had to give the IUSR user write access to that folder.


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And remember googlers -- IUSR not II_IUSR :) – Userpassword Aug 15 '12 at 15:53
@Userpassword, It's II_IUSRS not IUSR. IUSR didn't work for me, tested on win server 2012. – Pacerier Aug 27 '15 at 15:33
@AlHenderson, It's the file that needs write access, not the folder. (But setting folder will work too because the file will inherit permissions upwards.) – Pacerier Aug 27 '15 at 15:34

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