This is a very common case when the new user is not able to login to the system after his/her profile is created by Manager.
First thing that has to be checked is whether Role has ever been assigned to user profile as sometimes this step is missed by administrators and it results in inability to login to any store afterwards.
To assign a Role to User Role please follow next steps:
1. Go to Manage tab in your WS
2. Select Administration Tools
3. Click on User Administrator
4. Choose Role Assignment Manager tab and select newly created user from drop-down menu at the top portion of the screen
5. Once user is selected double click on Role you want to assign to this user
6. Click on Save button to save the changes.
NOTE: Do not assign multiple Roles to the same person as this will ruin the logic of your software.