From MobileX for SageCRM

A checklist to be used when a user cannot log on

1. User is allowed log on to CRM via CRM's web services (Allow WebService Access:True)

 Navigate to the users details (Administration -> Users -> Users) and view the users details and check that the
 "Allow WebService Access" setting is set to true

2. MobileX license check.

 Navigate to "Administration -> CRM Together -> MobileX "
 From that screen check that the user is in the list

3. You cannot use the ampersand '&' character or '%' character in a password when using MobileX (this is due to a web-service bug in Sage CRM).

Other strange characters may also be unsupported-remove all to test