If the posting, which Salary does, fails after a given payroll or payment, you will be able to see this in the menu Integrations -> Bookkeeping -> Choose View booking. Here all the postings done by Salary will show up:

If a posting, done by Salary, has failed, you can simply click Bookkeep again and then Salary will try to post in your bookkeeping system once again. Then the posting will be updated in 10 minutes' time. If, however, you have not mapped all the necessary accounts, you should make sure that this is done before trying to post again. When the mapping is missing you will receive a notification in the payroll where the posting failed. This will show up as an orange notification bar in the payroll.

If the posting succeeds after you have clicked Bookkeep again it will say Automatically bookkept.

Are you still experiencing problems with the posting? Do not hesitate to contact the support team.