If a user attempts to manually login to ProcessManager and incorrectly types their password multiple times their user account in Active Directory may get locked out. The number of failed attempts this will take to lock the account in Active Directory is dependent on the configuration of the Account Lockout policy in AD.
The authentication method ProcessManager uses in the shipped ServiceDesk 7.5 releases increments the BadPwdCount attribute twice for each attempt to login to the ProcessManager Portal.
This issue has been addressed via a Workflow rollup install for ServiceDesk 7.5 MP1. Please contact Symantec Technical Support and refer to this KB article to obtain the rollup.
The next version of ServiceDesk will ship with this fix included.