Yannis, as we already mentioned a blank screen is frequently due to a PHP fatal error.
So check your "error_log" file to get more info on the reason.

If you are creating a fresh slave site and that you have removed (deleted) the default joomla templates then after the "Joomla installer", you may also have a blank screen because the default joomla templates directory are missing.

Hello Edwin,

I have the same issue as mentioned above. Blank page when accessing the menu: 'Manage Sites, Models and Tools on'.
I did several clean installations of Joomla 2.5 (with & without FTP enabled...).

I've tried to show php error logs in the administrator/index.php file with following code but with no result:
ini_set ('track_errors', 1);
ini_set ('log_errors', 1);
ini_set ('error_log','/customers/3/a/2/mysite.net/httpd.www/php_error.log');

I contacted my hosting provider to solve this and he said that the extension may have a memory limit issue.
My hosting server has a 32MB of memory limit.

I don't have any access to a log error file.

Any help is really appreciated.

If you hosting provider had an error message with "out of memory", you can try increasing the memory size.

Our hosting provider has 256MB of memory.
We think that 128MB should be enought but sometime, during the replicatin of a DB and when the native MySQL copy can not be used, the content of the DB is stored in memory and the size might be higher and depend on the DB size.

I have the same issue any clue about this? I use joomla 2.5.8 and php 5.4.8.
The big problem here is when the system doesn't show any log so we can't know how we can track the error. Is php issue(memory, buffer, etc) Is permission issue(and where? Anyone can help?

Sorry but I am not able to reproduce it.

Initially test with WAMP and PHP 5.4.3, I have redid the test with PHP 5.4.13 and I didn't get any fatal error.

Perhaps that you can try enabling the Joomla debug mode and perhaps also try force the PHP setting to display all errors. So that, perhaps you would received somewhere more info on the error.

Yeah is very strange issue, doesn't have log and tells nothing like when you miss a " or }. But in another platforms(linux with php 5.4.8) it works . Maybe is a server related issue but we don't know what fix...