Hello! This issue may have triggered itself due to a Windows automatic update on to some the local machines of your customers. We also experienced this on internal 8.1 versions of Standard ERP and had made fixes for this in 8.3, 8.4 and 8.5. We recommend that your customer updates to the latest 8.5 version of Standard ERP for optimal system performance in their Windows environment. Thanks!

Best Regards,
Omar