Short answer
A watch rule applies a tested profile to eligible files while the desktop app is open. Keep input and output trees separate, filter unrelated formats and review a small first batch.
When to use this method
Watch folders suit repeated arrivals with the same known settings. They are not a background Windows service and do not run while the desktop app is closed.
How we checked this guideSee what we reviewed, what we confirmed, and where the feature stops.
- What we reviewed
- Reviewed watch rules, profile references, reconciliation after restart and output safeguards.
- What we confirmed
- New eligible files are processed while the GUI is running, and missed eligible files can be reconciled after the app starts again.
- Important limit
- Overlapping source and output trees can reprocess results. A deleted or changed profile can also invalidate a rule.
What you need before creating a watch folder
A watch folder is a normal folder the app monitors for eligible new files. It is not a Windows service: the Just Converter window must remain open. First convert one representative file by hand, inspect the output and save those exact settings as a profile. Use separate input and output folders so a result cannot return to the input and trigger another conversion.
Create a predictable watch rule
Test and save the profile
Run the exact conversion manually and verify the result before saving its settings.
Separate source and output trees
Do not write converted files back into a watched input path.
Filter eligible files
Include only the formats and naming pattern the profile is meant to handle.
Review restart reconciliation
Keep the app open for new arrivals and inspect files discovered after the next launch.
Checkpoint: prove the rule with one disposable file
Place one supported test file in the watched folder after its copy has finished. Confirm that exactly one expected output appears, the source remains available and the output does not return to the watched input tree. Only then allow the rule to process a larger folder.
If an expected file is not converted
Confirm that the app is open, the rule is enabled, the file matches the rule and the saved profile still passes the app's compatibility check, called preflight. Also check folder permissions and the per-file result. After a restart, reconciliation retries eligible missed files. It skips files that fail the rule, preflight, stability or permission checks.
Watch-rule problems
- Using overlapping input and output folders
- Watching partially copied files
- Assuming the rule runs after the app closes
Automation checks
- The profile still exists and produces a valid file.
- Only intended formats enter the rule.
- Results do not return to the watched source tree.
Just Converter
Attach a proven profile to an input folder, keep output separate and review every file processed while the app remains open.