Recently, I had an issue in AX 2012 feature pack version where posting from AR or AP module resulted in Trial balance update process stuck in InProcess state. The checkbox ‘Update balance during the posting process’ greyed out in Financial dimension sets form and you cannot uncheck or check it again. The resolution for all the trial balance issues is to install the hotfix KB 2864076. This hotfix has lot of other dependent objects, so extra care is required if you are installing the hotfix directly because it may affect your customized objects in current AX implementation.