751e44c4__Error_Codes___ServiceNow_Wiki__Description
[Error / Data Code] 49 / 52e [Error] AD_INVALID CREDENTIALS [Description] 
Indicates an Active Directory (AD) AcceptSecurityContext error, which is returned when the username is valid but the combination of password and user credential is invalid. This is the AD equivalent of LDAP error code 49.
LDAP Error Codes - ServiceNow Wiki
Description