Martin,
So it seems I was incorrect about the version. We've been on 5.13.5.8967 since it was released. The error cropped up on November 18th and oddly enough, it occurs roughly every 4–5 days. Looks like it's due again any time now. I'm going to update the service to the latest version (5.19.6). I'll report again in a week or so to see if that fixes the issue.
2022-03-20 18:58:51.383 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-03-16 11:17:20.983 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-03-12 05:12:10.326 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-03-08 08:28:42.626 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-03-04 03:46:37.610 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-02-28 07:23:04.736 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-02-24 11:06:54.036 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-02-19 04:07:49.520 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-02-15 05:58:25.253 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-02-11 09:25:42.660 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-02-07 03:39:05.603 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-02-02 04:47:06.890 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-01-28 22:15:27.926 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-01-24 14:23:39.216 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-01-20 03:27:59.610 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-01-14 16:37:36.646 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-01-09 16:36:48.400 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2022-01-05 00:07:44.363 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2021-12-31 15:51:41.320 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2021-12-26 16:52:33.290 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2021-12-22 00:43:29.366 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2021-12-17 15:50:13.850 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2021-12-10 21:22:01.770 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2021-12-06 15:17:22.690 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2021-12-01 19:30:12.376 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2021-11-27 02:09:00.553 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2021-11-22 19:59:36.603 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe
2021-11-18 12:31:50.200 Cannot use C:\Program Files\BtgDashboardControl\winscp.exe