session open failed

Hi, There are problems with session, Please give me some advice. Thank you! Mike System: PHP4.06 + Apache 1.3.20 Win32 + Win98 (the session configurations are default in php.ini) when the 1.php is running, the IE shows 2 errors as below: Warning: open(/tmp\sess_5176646ce5a800db9101970b80d507f6, O_RDWR) failed: m (2) in c:\program files\apache group\apache\htdocs\web1\1.php on line 2 Warning: Cannot add header information - headers already sent by (output started at c:\program files\apache group\apache\htdocs\web1\1.php:2) in c:\program files\apache group\apache\htdocs\web1\1.php on line 6 ------------------------------- The scripts of 1.php: (1.php and 2.php are under the same base directory) <? session_start(); require("html-head.inc"); $name="user"; session_register("name"); header("Location: 2.php"); /* let the IE automatically turn to the 2.php */ require("html-foot.inc"); ?> ------------------------------- The scripts of html-head.inc: <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>page title</title> </head> <body> ----- The scripts of html-foot.inc: </body> </html>