In case you were asking how to insert the HTTP header 'Authorization' into your request:
For UFT:
1 - select your resquest
2 - Properties / Event / BeforeApplyProtocolSettings / New Handler
3 -
public void StServiceCallActivity4_OnBeforeApplyProtocolSettings(object sender, HP.ST.Ext.WebServicesActivities.Models.StChannelsBindingStack args)
{
this.StServiceCallActivity4.HttpRequestHeaders.Add("Authorization","Basic d29tZXVzZXI6c29tZXBhc3M=");
}
// Warning StServiceCallActivity4 have to match the Service activity call you are modifying with this event.
4 - Reproduce for each request (I did not find a better solution for this unfortunatly)
Bonus: From there you can always get the user / password from input parameter and encode the String in the method.
For Soap UI:
1 - Open your request
2 - On the bottom tab called 'Header': Add a Header called 'Authorization' with the value 'Basic d29tZXVzZXI6c29tZXBhc3M='
Hope it's what you need