IE cannot display the webpage and Firefox goes Blank on Drupal 5.3

Thanks for the quick reply Doka, I increased the upload_max_filesize from 2M to 10M, the post_max_size from 8M to 30M and the memory_limt from 20M to 100M but nothing.

I enabled the error reporting in the index.php but still nothing.

I disabled the folowing modules in the db

Civicrm
Youtube cck
webforms
thickbox
statistics
simplenews
poll
panels

I still get the white screen of death.

I also get this errors in the apache error log:

[Sat Nov 10 04:33:32 2007] [error] PHP Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /home/panguadalu/domains/panguadalupe.org.mx/public_html/index.php:8) in /home/panguadalu/domains/panguadalupe.org.mx/public_html/includes/bootstrap.inc on line 862
[Sat Nov 10 04:33:32 2007] [error] PHP Warning: Cannot modify header information - headers already sent by (output started at /home/panguadalu/domains/panguadalupe.org.mx/public_html/index.php:8) in /home/panguadalu/domains/panguadalupe.org.mx/public_html/includes/bootstrap.inc on line 531
[Sat Nov 10 04:33:32 2007] [error] PHP Warning: Cannot modify header information - headers already sent by (output started at /home/panguadalu/domains/panguadalupe.org.mx/public_html/index.php:8) in /home/panguadalu/domains/panguadalupe.org.mx/public_html/includes/bootstrap.inc on line 532
[Sat Nov 10 04:33:32 2007] [error] PHP Warning: Cannot modify header information - headers already sent by (output started at /home/panguadalu/domains/panguadalupe.org.mx/public_html/index.php:8) in /home/panguadalu/domains/panguadalupe.org.mx/public_html/includes/bootstrap.inc on line 533
[Sat Nov 10 04:33:32 2007] [error] PHP Warning: Cannot modify header information - headers already sent by (output started at /home/panguadalu/domains/panguadalupe.org.mx/public_html/index.php:8) in /home/panguadalu/domains/panguadalupe.org.mx/public_html/includes/bootstrap.inc on line 534
[Sat Nov 10 04:33:32 2007] [error] PHP Warning: array_key_exists() [function.array-key-exists]: The second argument should be either an array or an object in /home/panguadalu/domains/panguadalupe.org.mx/public_html/includes/module.inc on line 217
[Sat Nov 10 04:33:32 2007] [error] PHP Warning: array_key_exists() [function.array-key-exists]: The second argument should be either an array or an object in /home/panguadalu/domains/panguadalupe.org.mx/public_html/includes/module.inc on line 217

Next are the lines from module.inc

207 /**
208  * Determine whether a given module exists.
209  *
210  * @param $module
211  *   The name of the module (without the .module extension).
212  * @return
213  *   TRUE if the module is both installed and enabled.
214  */
215 function module_exists($module) {
216   $list = module_list();
217   return array_key_exists($module, $list);
218 }

and from bootstrap.inc

521 /**
522  * Set HTTP headers in preparation for a page response.
523  *
524  * Authenticated users are always given a 'no-cache' header, and will
525  * fetch a fresh page on every request.  This prevents authenticated
526  * users seeing locally cached pages that show them as logged out.
527  *
528  * @see page_set_cache
529  */
530 function drupal_page_header() {
531   header("Expires: Sun, 19 Nov 1978 05:00:00 GMT");
532   header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
533   header("Cache-Control: store, no-cache, must-revalidate");
534   header("Cache-Control: post-check=0, pre-check=0", FALSE);
535 }