Each of the tabs in the MDS Validator are described below:

Validator Version Information

DDict Version: 4.73


When first running the validation, this tab shows you the following:

Name and location of file being validated
Record Count:
Total number of lines and count of processed lines
Start Time:
Time validation started
Running Time:
Run time of validation (increases while validation running)

Once some basic file integrity checks (which can take some time) are complete, the following additional information is shown:

File Type:
The validator can validate different types of files, this indicates the type of the current file
File Version:
Version as reported by the current file header
Start Date:
Start date as reported by current file header
End Date:
End date as reported by current file header
Jurisdiction as reported by current file header


Once the initial file integrity checks are completed this page provides an indication of progress. It lists the various processing steps and an overall indication of progress as a graph. At completion it will tell you the name of the file to submit.

Record Integrity

This tab presents a tabular breakdown by record type (types depend on the file being validated) of detected issues with the file being validated. Note that it reports in real time so it can be viewed while the validation run is in progress. Doing so can save you from validating an entire file for which it is already evident a rebuild is required.

The various issues summarised are:

The record was validated without problems
The record had at least one issue that renders it undecipherable.
Examples include: short lines, bad record types or invalid key fields
The record did not have a parent in the submitted file. This can occur if the parent record exists but has irredeemable errors
The record was a duplicate, there were two or more records with the same key fields
The record is expected to have child records but there are none present. This can occur if the child record exists but has irredeemable errors
The record had at least one incorrectly supplied non-key field.
Examples include: illegal characters, incorrectly formatted numbers, out of domain values and invalid dates
The record had at least one issue to be investigated. See Reports
Examples include: Missing, zero and inconsistent values


The error table displays counts of all validation errors arranged into various groupings. The counts link to a listing of errors in each given grouping, so that the details can be examined.

Error Classes:


There are two components to this tab. The "line" box allows you to enter a line number in the file and view that line with the validator. The other component is the line viewer which displays the line layout. This second component is also used for viewing records linked to from the "By Record Type" and "Errors" tabs.

Each line reported through the viewer is partitioned into fields. Hovering your mouse over each one will provide more detail as well as any errors detected (in orange or red).

A summary of the status of each record is provided, the information reported is:

Line Number:
Line number within the validated file
Indicates if the line was OK, Malformed, etc.

Then a detailed list of each error (if any) is listed. Hovering your mouse over the list of errors will highlight the appropriate location within the record to assist with finding errors.

Running Historical Checks

The MHE file has various "Historical" logical checks defined. These use data from the previous year and check for changes and variations. They also provide additional reports on the "Reports page.

Online Validator:

Upload a DAT file for the prior year. Once it has completed validation, return to the later year in the "File" view. A "Revalidate" button should be visible, with the text: "Revalidation: This file could be revalidated to take advantage of your recently uploaded file".

Press Revalidate, and a message like "Your file (MHE___200800001.DAT) is revalidating. Please check the file history page in a few minutes" should appear. Once the revalidation is complete, the warning message will be gone and the Historical file used will appear in the Progress messages, eg. "using MHE___200700001.DAT for historicals".

You can tell if the checks have been run on the "Progress" page. If a source for the previous year was found the message will be like:

Running logical checks using MHE???200700001.DAT for historicals

If no source was found then the message will be:

Running logical checks (skipping historical checks)

Support Information

If you require more assistance, contact us by email and provide as much detail as possible regarding the nature of your problem. Please include the version information from the top of this page in your report. Screenshots illustrating your issue will be appreciated.