komme nicht ins backend

[azumed]

habe xt commerce 3 installiert, die üblichen probleme gefixt (tmp ordner, schreibschutz der configure usw.) frontend wird jetzt ohne fehler angezeigt. alles prima.
wenn ich ins backend will (localhost/xtcommerce/admin/index.php wenn mich nicht alles täuscht) bekomm ich folgenden fehlercode:

Warning: session_start() [function.session-start]: open(/tmp\sess_9137a6f79d505a7ef42a0a4d37f21bf5, O_RDWR) failed: No such file or directory (2) in C:\Xampp\htdocs\xtcommerce\admin\includes\applicat ion_top.php on line 338

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at C:\Xampp\htdocs\xtcommerce\admin\includes\applicat ion_top.php:338) in C:\Xampp\htdocs\xtcommerce\admin\includes\applicat ion_top.php on line 338

Warning: Cannot modify header information - headers already sent by (output started at C:\Xampp\htdocs\xtcommerce\admin\includes\applicat ion_top.php:338) in C:\Xampp\htdocs\xtcommerce\admin\includes\function s\general.php on line 130

Warning: Unknown: open(/tmp\sess_9137a6f79d505a7ef42a0a4d37f21bf5, O_RDWR) failed: No such file or directory (2) in Unknown on line 0

Warning: Unknown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct (/tmp) in Unknown on line 0

weiß nicht mehr weiter =)