Why on an AP Vendor Payment are the SUBMIT and the POST buttons grayed out? Why can't I post?
When processing an AP payment using the System Check Payment Method, both the SUBMIT and POST buttons will be grayed out. The reason for this is that the method for posting a system check is by generating and printing the check. Only the System Check Payment Method is handled this way, all other Payment Methods would be submitted and/or posted and these buttons will be available for use in those instances.
In the top right of your vendor payment edit screen you'll note the status is INUSE and the comment that Check Has Not Been Printed.
Resolution: To complete this process you must print the check. When you have completed the check printing process, your payment will be posted to the general ledger. See the links below for more information about printing checks.