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File Converters
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A repeatable EML-to-PDF workflow needs a defined input folder, an output folder for each run, explicit attachment choices, and a check of the result. CoolUtils Total Mail Converter supports batch conversion and a command-line interface on Windows. The useful starting point is a small, predictable export that you can inspect before using the same settings for a larger collection.
Keep the original EML files available. Put converted PDFs in a separate location so you can compare the source and output, investigate a failed message, or repeat a run without mixing old and new results.
Set up one conversion run
Create separate locations for input, output, and run notes. For example:
C:\EmailExport\
Input\
Output\
run-001\
Run-notes\
This is a suggested working arrangement, not a folder structure that the converter creates automatically. Create the output folder before running the examples below.
Begin with copies of a few EML files. Include messages that resemble your everyday input: a plain message, an HTML email, and a message with an attachment. If incoming files normally live in subfolders, include that case in your initial check.
Make a short note of the source location, the application version, and the intended result. "Separate PDF for each message; save original attachments" is more useful than "convert everything."
Convert a single EML before using a wildcard
Install CoolUtils Total Mail Converter, then open Windows Command Prompt in the folder containing its executable. If you run it from another location, use the full path to the installed executable.
The command-line reference uses a source, a destination, and output options. This example requests PDF output for one EML:
MailConverter.exe "C:\EmailExport\Input\message.eml" "C:\EmailExport\Output\run-001" -c PDF
Replace the source path with a file you have prepared. Open the resulting PDF and compare it with that message. Check the subject, sender, date, body text, and any content that matters to the recipient.
The command selects PDF output. Attachment handling and the rest of the export configuration still need attention; choosing PDF alone does not specify every part of the deliverable.
Once that result is suitable, use a wildcard to select EML files in the input folder:
MailConverter.exe "C:\EmailExport\Input\*.eml" "C:\EmailExport\Output\run-002" -c PDF
Create the new destination folder first. Keep quotation marks around paths, particularly when they contain spaces. If you need files from nested folders, configure subfolder processing explicitly instead of assuming that the wildcard includes them.
Choose the structure and attachment behavior
The command-line reference documents controls for subfolders, preserving folder structure, combining messages, and naming output files. Decide which result you need before adding those options to a recurring job.
| Decision | Example of an intended result | Verification |
|---|---|---|
| Input scope | EML files from one folder and selected subfolders | The expected source messages are included |
| PDF grouping | A separate PDF for each message | Each selected message has a corresponding PDF |
| Attachments | Original attached files saved beside the export | Files open and can be matched to their messages |
| Output names | Names that distinguish messages with the same subject | Repeated subjects do not create ambiguous results |
Total Mail Converter can save attachments; conversion of supported attached documents is documented as a Pro feature. Use the attachment workflow guide to choose between separate files and converted content.
Do not use an attachment filename printed in the email header as your only evidence that the attachment was exported. Locate the saved original or the converted pages and open them.
For messages containing remote images, decide whether those images should be loaded. The command-line reference includes a control for disabling that access. A local desktop conversion and a job that makes no network requests are different requirements, so verify the setting if the distinction matters to your workflow.
Keep a log and a short run record
The command-line documentation includes logging, verbosity, and append-or-overwrite controls. Configure them using the help for the installed version, then confirm where the log is written. Do this before moving the job into a recurring process.
Logging can change how errors are presented. The reference describes an option that writes errors to a log instead of displaying them, which makes reviewing that file part of the workflow.
For each run, record:
- The application version and conversion command used.
- The source folder and number of selected messages.
- The output location and attachment choice.
- Any reported failures and the files that need another attempt.
Keep those notes with the run, even when there are no reported errors. An empty error log cannot tell you that every expected message was selected or that a wide table is readable.
If you need a detailed record, confirm that the log contains the information you expect before relying on it. Avoid treating a log filename as proof of a complete audit trail.
Reconcile the result with the selected messages
Count messages and attachments separately. In a workflow configured for one PDF per message, with every source message converted successfully, the message-PDF count should match the selected message count. Additional files may be expected when attachments are saved separately.
For example, a collection of 12 messages could produce 12 message PDFs and several original attachment files. Counting every file in the output folder as a converted email would give you the wrong result.
Open a selection of PDFs from across the run, including the cases you checked at the start. Review any message mentioned in an error log individually. Confirm that filenames distinguish messages with identical subjects and that links to separate attachments work from the delivery location.
If you combine the messages into one PDF, a file count no longer checks coverage. You need to verify the included messages within that document.
Repeat a run without mixing the results
Use a new output folder when you change settings or retry an export. This keeps the earlier result available for comparison and avoids confusion about which run produced a particular file.
The converter documents options for deleting originals and forcing overwrites. Leave those out of a routine export command unless you have deliberately chosen that behavior and have a recovery method. A conversion job does not need to remove its source files to produce useful PDFs.
When the input format or application version changes, repeat the representative sample check. That gives you a chance to catch different rendering or output behavior before applying it to the full collection.
Moving from a desktop job to a server workflow
A command-line interface does not, by itself, define the right product or license for a server deployment. CoolUtils has a separate Total Mail Converter X guide for EML-to-PDF command-line conversion.
Use that product documentation when planning a server job. Establish the working export first, then decide how it will be scheduled and monitored in your environment.
For a desktop workflow, start with the sample messages and confirm the PDF and attachment result before expanding the run.
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