Internal Server Error

I am trying to export this grid to XLS:
extras.ha.uth.gr/shoah/el/grid.php?qid=70

However, I get an Internal Server Error (500).
The debuf file shows all the grid data, so up to there the script works perfectly. An empty php*.tmp file is also created.

The online generator does not work as IE prohibits it due to cross-scripting. Firefox doesn’t work either, but no error message is generated.

Export to PDF works fine.

I have tried grids as small as two lines, thinking there may be a php memory issue as discussed in another thread, but there is no difference.

Please, check permissions of directory extras.ha.uth.gr/shoah/resources … exportxls/
It looks like this directory does not allow contents to be listed.

Still, no change…

Oh, there is a change. The tmp*.php files are no longer there after the error.

Still there isn’t access to extras.ha.uth.gr/shoah/resources … nerate.php file.
ERROR
The requested URL could not be retrieved