admin-panel - most sites doesnt work more!

Hi!

i have today installed a mod, and after this the half of my sites in admin-panel doesnt works more.
the developer said the mod have nothing to do with the functions of admin-panel.. 

so the error is this:
if i want open in admin-panel this sites, than i see just a white site! 

http://www.mysite.com/administration/profiles.php 
http://www.mysite.com/administration/basic_settings.php
http://www.mysite.com/administration/advanced_settings.php
http://www.mysite.com/m/news/admin/
etc.

some other sites are working... like:
http://www.mysite.com/administration/flash.php
http://www.mysite.com/administration/memb_levels.php

its very strange. have somebody the same problem? how i can fix it? any ideas? 
i havent a backup, so i hope that somebody have a good idea.. 

best regards from germany!

A blank white page usually means an error is occurring. Your not seeing the error because you most likely have php on your server configured not to show errors. Most likely php is logging them instead.

So go through the sites php error logs or turn on the display errors option.

Your host can tell you where that stuff is located if your can't find it.

thank you!

now i got a error and i have fixed it. i had a problem with this file:
/inc/params.inc.php

done!

best regards and wish you a nice day! :D

E:// @Rope man, correct. Sry. i have forgot to post it: ... let me check again, what the error exactly was.

What was your error?  It's helpful it to others in the future if they know what the error was and how you fixed it specifically.

I got a error that i have a problem with /inc/params.inc.php on line 95.

THIS LINE: 
require_once( BX_DIRECTORY_PATH_ROOT . "templates/tmpl_" . $tmpl . "/scripts/BxTemplConfig.php" );

I have checked my templates ordner, and i have saw that how ever the file BxTemplConfig.php
was deleted from my custom-design from tmpl_xyx and the order tmpl_uni was full deleted! ^^

I have add the file and the order and all works fine!

the mod i have reinstalled and now it works great too. i dont want to said which mod it was, because i believe,
i have made a fault and i dont want that his image is little bit destroyed. :D
hope you understand it.

best regards! (ps: sry. for my bad english)

thanks................