What's the error?  Normally posting issues from a workstation are related to Paperless Office, but there should be an error in that case.

User gets this message AFTER printing the transaction entry but doesn't get a prompt to post to the daily transaction register.

User did not get any error messages.

User is able to process Bill of Material entries without problem.

Looks like they answered "no" to the question the first time, and the data is sitting in the General Ledger Module and now needs to be printed and updated form the General Ledger --> Main Menu --> Daily Transaction Register.  
Or the user did not post the subsidiary module register/journal so no GL Posting yet. 
Or you have turned on "auto post" to the General Ledger in User Role Maintenance for that module and it already posted.