We have several File trigger jobs, monitoring several different paths/folders for specific files.. For the most part, they work as expected, however at times, the triggers do not fire. No errors, just files get ignored, and subsequent files will work, and so on.
This has been happening for quite some time, and can't figure out why? Why would it work for 100 files or more, then all of a sudden ignore one, then work again! Trigger uses a file mask, nothing special about the files that get ignored, and if I manually run the file trigger, the job will work!
Example of files myfile1234.csv mask myfile*.csv
Any suggestions, thoughts are appreciated.

Thanks.

Control character in the filename that is not visible?

Hi, thanks for the feedback. Not sure what you mean, but when there is a file missed if I fire the trigger manually it will run.
Appreciate the feedback and any suggestions you have.

I should have been more specific. When strange things like this happen I usually check for the unexpected like a space or other invisible characters in the name. It may depend on how the name gets created. If users are entering a name, then a fat-finger could introduce a control character (like a TAB) that could be part of the name but invisible to the naked eye. The same character may affect the processing of the trigger, but not when run manually. Just something to check and rule out. I've seen this situation cause issues in my career so it's always on my mind to check when weird stuff happens.

Dump the name out in hex to see if what is there is really what you expect.

Thanks for the explanation. These files are system generated and I'm using a wild card for the trigger. File0001.csv, File0002.csv, etc..
I have removed the file name on this one job, and just made it *.* to rule out name issue.
Waiting now on the one job..

Thanks for the explanation. These files are system generated and I'm using a wild card for the trigger. File0001.csv, File0002.csv, etc..
I have removed the file name on this one job, and just made it *.* to rule out name issue.
Waiting now on the one job..

I recommend downloading something called FileSystemWatcher and monitor that folder - then you will see exactly what happens in the folder, and in the vast majority of cases you'll see something unexpected that explains why it misses it.