Dynamics 365 CSV over 8 MB: split it and check the delimiter

Stay below 8 MB and preserve the mapping clues

The default maximum import-file size documented for Dynamics 365 Customer Insights is 8 MB. Use a target around 7.5 MB, then check the delimiter and required fields because a size-safe file can still fail mapping.

• More than 8 MB: split by size.
• Fields appear in one column: confirm comma or semicolon delimiter selection.
• The record is rejected: check required fields and alternate-key columns.

• Find CSV rows with inconsistent column counts →Diagnose malformed rows before uploading them to a platform.
• Check or convert the CSV character encoding →Use this when Japanese, Korean, or accented text is garbled after export.

Check delimiter, header, and required fields

Microsoft's import guidance expects a .csv extension, a single header row, and delimiters that match the import setting. Keep the first line free of quoted field names and make sure each record type has its required fields mapped.

• Choose the delimiter used by the export; do not assume comma when the file uses semicolon.
• Keep one record type per import file where the mapping requires it.
• Use an alternate key only when the source column is stable and unique.

• Find CSV rows with inconsistent column counts →Diagnose malformed rows before uploading them to a platform.

Split the export in LocaCSV

LocaCSV does not guess which Dynamics fields are required. It gives you the smaller files and the counts so you can make that mapping decision in the official import screen.

1. 1Save the Dynamics 365 export and retain the original for rollback.
2. 2Open the size split workspace and select the CSV.
3. 3Enter 7.5 MB or a lower target, then run the split.
4. 4Open the first output and confirm its delimiter, header, and required fields before continuing.

Reconcile the output before mapping

• Every part is below 8 MB with a safety margin.
• The input and output row counts reconcile.
• Headers, delimiters, required fields, and alternate-key values are intact.
• A small test part maps correctly before the remaining files are imported.

• Find CSV rows with inconsistent column counts →Diagnose malformed rows before uploading them to a platform.
• Check or convert the CSV character encoding →Use this when Japanese, Korean, or accented text is garbled after export.

If the import screen shows one wide column

Do not split again. The usual cause is a delimiter mismatch or an encoding problem. Confirm the delimiter in LocaCSV's diagnosis, convert the encoding if necessary, and then re-open the corrected sample.

• Find CSV rows with inconsistent column counts →Diagnose malformed rows before uploading them to a platform.
• Check or convert the CSV character encoding →Use this when Japanese, Korean, or accented text is garbled after export.

Hand Dynamics 365 a mapping-ready file

After the size, delimiter, and row checks pass, finish the mapping in Dynamics 365 and review the successful and failed counts separately.