When a trail runs
A trail runs when a file arrives, on a schedule, or both. Timing, schedules, files already in the folder, and when a trail stops itself.
By Operelio team · Updated September 2026
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Three ways to start a run
| Choice | What happens |
|---|---|
| A file arrives | Every file that lands in the folder starts its own run, usually within a few minutes. |
| On a schedule | Runs at a set time and picks up what is waiting, up to 25 files each time. |
| Both | Arrivals usually run within a few minutes, and the schedule picks up anything still waiting. |
How soon a file is picked up
Operelio waits until a file has been in the folder for 3 minutes, so a file still uploading, or several arriving together, is not run half-written. On a trail that runs when a file arrives, the next pass after that starts its run.
A trail starts up to 25 runs in one pass. A bigger batch goes through over the next few passes.
A run that stops keeps its file in almost every case, and the trail does not pick that file up again. To carry on with it, fix the run.
Schedules
A schedule runs every day, every weekday, on one day of the week, or every 6, 8 or 12 hours, always on the hour. No schedule runs more often than every 6 hours.
Each trail keeps its own time zone. A time that a clock change skips runs at the next valid time, and a time that happens twice runs once.
If your monthly jobs have run out at the scheduled time, the trail records that and skips that run. If nothing new is waiting, it records that it found nothing. Neither uses a job.
Files already in the folder
When you switch a trail on and its folder already holds files the trail has not run, it asks what to do with them.
| Answer | What happens |
|---|---|
| Only files that arrive from now on | The default. The trail leaves those files alone. To put one through later, take it out of the folder and add it back. |
| These N files as well | N is the number waiting. They go through the next time the trail runs, up to 25 at a time. The dialog shows how many jobs that can use, out of what you have left this month. |
When a trail stops itself
A problem with one file stops that run, and the trail carries on with the next file.
The same failure at the same step on two runs, with no clean run in between, stops the whole trail. A problem with the trail itself, like a lost CRM connection or a missing mapping, stops it the first time. Missing columns, and a push that only partly lands, stop only the run they happened in.
A stopped trail shows Needs attention, and new files wait in the folder. The people who hear about the trail get an email with the reason and a link to it, unless that notice is switched off for the trail.
Waiting for room is not a failure. If too many jobs are running at once, or your jobs for the month run out part way through, the run waits and carries on once it can.
If your plan stops including live trails, Operelio pauses the trail and emails the reason, unless that notice is switched off for the trail.
Frequently asked questions
Can a trail run every hour?
Not on a schedule. The shortest interval is every 6 hours. Set the trail to run when a file arrives and each file usually starts within a few minutes instead.
What happens to files that arrive while a trail is paused?
They wait in the folder. When you switch the trail back on, it asks whether they go through.
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