Install in subdir

[محروم.كوم]

I recently installed phowebsite (1.6.3) in a subdir of my domain* lets say www.mydomain.com/subdir. In the root of my domain I have an index.php file with the following line:
Code:

Now when I login I am returned www.mydomain.com/subdir with a 404 error. I have to manually add the index.php (or remove subdir from the URL).

Logging off has the same effect. Where in the configuration did I do something wrong? __DEFINE_LIKE_SHARE__