Today I tried to create a new web application from Sharepoint 2010 central administration and I got this error
"The password supplied with the username <domain> was not correct. Verify that it was entered correctly and try again" Error while creating web application in SharePoint 2010</domain>
I remembered that I have changed my password two days ago and that was the cause of the problem. The following command line got things working properly again
stsadm -o updatefarmcredentials -userlogin <domain> -password <newpassword></newpassword></domain>
Hope that will help