If you have already opened a pre-authorisation for a card, it is important that this is either used or voided off before running the end of day Z report.
Failure to do so will result in being prompted at the point of running the Z report with the following:-
Open tabs with a small card symbol next to them are active tabs with pre-auths pending against them. Read further on voiding pre-authorisations here.
Should you receive this error message when you have no tabs marked with active pre-auths,then please contact email@example.com for further assistance.