Guide / File preparation

Why an upload is refused before any checks run

A wrong file type, UTF-16 text, an empty file or a file over the size limit is refused before any checks run. Here is how to fix each.

TMH18 Validator • 3 min read • Reviewed

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About 3 minutes. A narrated explainer; the same words are below.

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  1. 0:00Sometimes you upload a survey file and get a refusal. No findings, no checks.
  2. 0:06It means the file was not accepted for checking, not that the survey is wrong.
  3. 0:12Think of a door that checks the key before anyone looks inside.
  4. 0:16A refused file never gets in, so the checks never see it.
  5. 0:21Validation is different: an accepted file is then tested rule by rule.
  6. 0:28Refused means not accepted. Checked means accepted and tested.
  7. 0:34First, the file type. TMH18 Validator accepts C S V, TMH 14 files, and fifteen TMH 18 file types.
  8. 0:42Any other extension is refused, and so is a file with none.
  9. 0:46A spreadsheet saved as X L S X is refused this way.
  10. 0:53Second, the text encoding. TMH 18 version four asks for plain text in UTF-8.
  11. 1:00UTF-16 is refused, with or without a hidden marker. A UTF-8 marker is simply removed.
  12. 1:08An empty file is refused too.
  13. 1:11Third, size. Read the limit in the Before you upload panel.
  14. 1:17It depends on your organisation's setup, so compare your file first.
  15. 1:22To fix a refusal, change the file, not the rules.
  16. 1:26Export the spreadsheet to C S V, save text as UTF-8, and confirm the file has content.
  17. 1:34Then choose Upload and validate.
  18. 1:39Say a team saves its sheet as Unicode Text, and the upload is refused.
  19. 1:44They re-export as UTF-8 C S V and upload again.
  20. 1:50This time it is accepted, and the checks run.
  21. 1:54A file type that differs from the chosen template is not a refusal. Checks run, with a warning.
  22. 2:01You choose the template yourself, so match it to your survey.
  23. 2:06Getting through the door is only the start. An accepted file can still hold wrong data.
  24. 2:11A skipped check is not a pass.
  25. 2:14Certification records a review decision. It does not prove the measurements are right.
  26. 2:20So: the right type, UTF-8 text, real content, under the limit.
  27. 2:26Fix the file, then upload again. The full guide is at TMH18 dot com, slash articles.

Refused at upload is not the same as checked

Some files stop at the door. TMH18 Validator checks the file type and the text encoding before it runs any rules. Encoding is the way text characters are stored in the file. If the file fails that first look, no checks run and no findings are produced. This is separate from TMH 18 data validation, where a file is accepted and then tested rule by rule.

Keep the two ideas apart. A completed transfer is not a completed check, and a check that was skipped is not a pass. A refusal tells you only that the file could not be read in the first place. It says nothing about the survey data inside it.

Which file types are accepted?

TMH18 Validator accepts .csv files, TMH 14 files ending in .rsv or .rss, and the TMH 18 data file types it has check templates for, such as .cid, .fwd, .net, .rcl and .lan. Any other extension is refused with a message that starts: File type ".x" is not accepted. A file with no extension at all is refused too.

A spreadsheet saved as .xlsx is the usual cause. Open it, export the sheet as CSV, and upload the exported file. Keep the original workbook as your source.

  • Check the extension after the final dot in the file name
  • Export spreadsheets to CSV before uploading
  • Use the exact extension of the TMH 18 file family, such as .cid or .fwd

Is the text UTF-8 and not empty?

UTF-8 is a common way of storing text characters. TMH 18, version 4 (headed "Draft Version 4", October 2014) section 1.1 requires data files in plain text in UTF-8. TMH18 Validator refuses a UTF-16 file, whether or not it carries a byte order mark, which is a short hidden marker at the start of a file. Excel can create UTF-16 when you choose Save as Unicode Text. A UTF-8 file that starts with a byte order mark is not a problem. The mark is removed for you.

An empty file is refused as well. If the picker says the file looks empty, the export probably failed. Run it again and check that the file has content before you upload.

  • Save the export as UTF-8 text, not Unicode Text
  • Open the file in a text editor to confirm it has content
  • Re-export rather than editing the encoding by hand when you can

Check the size limit and the template

Open Upload a file and read the size limit in the Before you upload panel. A file over the limit is refused. The limit depends on how TMH18 Validator is set up for your organisation, so this guide gives no number. Compare your file with the limit before you start the transfer.

The check template is your choice. If the file extension differs from the template, the upload still goes ahead and a warning, UPLOAD-EXT-MISMATCH, is added. A .csv file never triggers it. This is a warning, not a refusal. The guide on choosing the check template covers it in depth.

What to do after a refusal

Change the file, not the rules. Fix the type or the encoding at the source, export again and upload the new file. Once a file is accepted and its checks have run, the findings show what passed, what needs action and what was skipped.

Acceptance is only the start. A file that gets through the door can still contain the wrong data, and certification records a review decision, not proof that the measurements are right.

Put it into practice

Upload a file

Sign-in and the relevant account permissions are required.

File preparation

Prepare your survey CSV for validation

Match the check template, protect your source values and check the exported text before uploading.

Validation

What errors, warnings and skipped checks mean

Read a validation result in context and decide whether to correct the source, investigate further or record an allowed exception.

Certification

From reviewed survey file to certificate

Understand the co-sign and final certification steps, who can act, and what to include in the handover.

Validation

Choosing the check template for a TMH 18 survey file

You pick the check template on the upload form. Learn what it controls, what a file type warning means, and how to check a file against the right template.

Standard

TMH 18 data validation: from survey file to certificate

TMH 18 data validation explained: what version 4 of the standard defines, what TMH18 Validator accepts and checks, and what a certificate does and does not tell you.

File preparation

TMH 18 file format: semicolons, UTF-8 and empty fields

The TMH 18 file format has three record rules: UTF-8 text, a semicolon between fields and no missing fields. See how to follow them and what the check menu offers.

Standard

Why every TMH 18 record must fit inside the network kilometres

The TMH 18 network file sets each road's km range. See what the standard says about data outside it, and what TMH18 Validator does not confirm.

Certification

What a TMH18 Validator certificate tells the client

Road survey data certification here is a review decision plus a SHA-256 fingerprint of one file. See what it proves, what it does not, and how to check it.

Certification

When nobody in your team can issue the final certificate

Separation of duties for survey files: who may certify, the warnings TMH18 Validator shows early, and how to invite a second certifier.

Validation

When to record an exception on a finding, and what to write

Record exception clears a finding so a file can move on, but you cannot undo it. See who can use it, what reason to write, and why a Reupload or a new run of the checks drops every exception.