Hi, win 2003 server, IIS, php 5.2.1, mysql 5.0.18, Sugar Version 4.5.1h (Build 1104))

In calls, at saving time, a user received the displayNoAccess message and after a seconds set him to the main screen.

The sugarcrm.log doesnt show any uncommon message.
log4php.properties:
log4php.rootLogger=fatal, A2
log4php.rootLogger=error, A2
log4php.rootLogger=warn, A2
//log4php.rootLogger=info, A2
//log4php.rootLogger=debug, A2

Whats the common reason(s) to receive the message?

TIA,

Grenville Tryon