PHP: Problem mit session_start()

[Neolix]

Ich bin noch relativ neu in PHP und vermute, dass ich PHP falsch konfiguriert habe.
Wenn ich per session_start eine session starten will, krieg ich diese fehler:

Warning: session_start(): open(C:\PHP\sessiondata\sess_c501b20da6427fa6bd2231afb8373c5a, O_RDWR) failed: No such file or directory (2) in E:\Apache Group\Apache2\htdocs\shop\index.php on line 11

Warning: session_start(): Cannot send session cookie - headers already sent by (output started at E:\Apache Group\Apache2\htdocs\shop\index.php:6) in E:\Apache Group\Apache2\htdocs\shop\index.php on line 11

Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at E:\Apache Group\Apache2\htdocs\shop\index.php:6) in E:\Apache Group\Apache2\htdocs\shop\index.php on line 11

Warning: Unknown(): open(C:\PHP\sessiondata\sess_c501b20da6427fa6bd2231afb8373c5a, 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 (C:\PHP\sessiondata) in Unknown on line 0

Was heißt das?

P.S.: PHP ist bei mir unter E:\PHP installiert

mfg und danke im vorraus
Neolix