Cannot install Joomla 2.51 if session.save_handler is set to sqlite and session.save_path is session.sdb. It seens Joomla do not recognize this option for sessions correctly:
Failed to write session data (files). Please verify that the current setting of session.save_path is correct (C:\Program Files (x86)\Zend\ZendServer\tmp\session.sdb)
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open(C:\Program Files (x86)\Zend\ZendServer\tmp\session.sdb\sess_m8rsoc9q6ap2nsh9jkelrfdqb3, O_RDWR) fa
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So far i had no issues with this PHP Settings.
I have now set both to standard values with ini_set (files,tmp path), now everything works fine.