I just started working with LoadRunner using trail version. I was able to successfully develop few Scripts using VuGen which ran successfully earlier but are failing now for the following reason:

Error in Test Results:
Access Denied(Authentication failed): Your credentials could not be authenticated. No Credential supplied....This is typically caused by incorrect User Name and password.

Error in the Log:
vuser_init.c(9): Error -26547: Authentication required, please use web_set_user, e.g. web_set_user("Domain\\user", "password", "hostort"); [MsgId: MERR-26547]

FYI, My login is working fine with Mercury tours website and Yahoo website that I have developed the scripts but for some reason script is failing. My UserID and password are displayed properly in the log. I used Web(HTTP/HTML) protocol for this.

I have devloped another script using Windows sockets protocol on Flight sample and it is working fine.

Can anyone tell me the reason why it is failing?

Thanks in advance.