First, get the full error from the Charge Processing Batch Summary Report.  At the end of the report will be the Informational and Warning messages.  Warning messages trigger this error.  The Charge Processing Summary report has a file name like "udchgsumYYYYMMDDHHMMSS.pdf", for example "udchgsum20170310090609.pdf".

Example of a report's warnings:
 
The following errors and messages resulted from the processing of CHG - XXXXX:
 
Error     Message                                             Error Level
-----------------------------------------------------------------------------
CH200     Automated settlement request for Merchant           W
          ID:332078107941, Count:10, Net:546 not approved.
          Vendor Reference ID:AIFGFWV0AJ,
          Message:BATCH OUT OF BALANCE, Count:57,
          Net:3323

You can also get the error by checking the CHARGE_LOG_ERRORS table:
 
SELECT * FROM   CHARGE_LOG_ERRORS
WHERE  PROCESS_ID = 'CHG - XXXXX';

The message will be listed with an Error_Level = 'W'.

Action to take:  Wait 25 minutes (after the Charge Processing job), then check the Sage Virtual Terminal.  You should see the settled batch under Reporting, Settled Batches. If there was a bad batch, you would see it with a status of "Pending" when you go to Reporting, Current Batch. However, if the batch did not settle after 25 minutes, Sage is notified immediately. They will research/rectify the situation within 24 hours and contact you to confirm that they have done so.