A fair trade retail store contacted us on several occasions regarding their POS Computer ‘locking up’. This would only happen during customer transactions. The customers impacted would have to wait for the volunteer to fumble with the computer and/or seek assistance from one of the volunteer managers. The staff did not know how to resolve the issue so they would physically power down the computer without gracefully shutting down the operating system first.

We made several trips to the store to review the system and application event logs. As volunteers for the store, we also waited to experience the behavior for ourselves. But, we never witnessed it nor found any errors to indicate a problem.

We created a guide, complete with screen shots, to instruct the volunteers on options to cancel processes that were not responding and to restart the computer using various methods in case the mouse or keyboard ceased functionings. While developing the guide, we finally reproduced the issue and demonstrated the behavior to one of the managers who had repeatedly reported the problem. As it turned out, volunteers would occassionally bump the mouse and cause it to lose focus on the POS application. This would prevent the bar code scanner from working and give the appearance that the computer was ‘locked up’ (although the software, operating system, and hardware were all fully-functional). The first step in our troubleshooting guide was simply to move the mouse and click on the POS application in order to resume the sales transaction. No issues have been reported since the guide was delivered.