During Dataverse data import (CSV) in the modern UCI import experience, users may hit a mapping/validation failure at the “Review Mapping” step. In some cases, the error message displayed to the user contains unreplaced placeholder tokens such as {0} and {1} (for example, “This field can not map {0} {1}, please fix it and try again”).

{0} and {1} are placeholders in the message template that should represent real values (e.g., field name / entity name), but the UI does not replace them with the actual values at the time the error is shown.

Because the UI error text is non-actionable, customers cannot identify which column/field caused the failure and are blocked from self-troubleshooting. This increases support load and prolongs resolution time, especially for large files or many columns, and for customers who cannot easily interpret raw network traces.

Today, the only way to infer what {0} / {1} represent is to:

• Inspect the network trace to find the parameters returned by the service, and map them back to the problematic field/entity; and/or
• Navigate to Advanced Settings → Data Management → Imports and check the failure details; and/or
• Navigate to Advanced Settings → System Jobs (type “Import”) and check the detailed message.
• 
  

These steps require admin access and technical skills, and are not realistic for many end users.

Requested improvement

Enhance the Import (UCI) error messaging at “Review Mapping” to be actionable by default:

1. Replace {0}, {1}, … placeholders with the actual runtime values (e.g., table name, column/field name, source column header, invalid value).
2. When substitution is not possible, show a structured message with explicit fields such as:

• “Unmapped source column: ”
• “Target field: ”
• “Reason: ”

1. Provide a direct link/button to open the relevant Import record’s Failures details from the UI, so users can immediately see which row/field failed without switching tools.
2. (Optional) Include a correlation/request ID in the UI error dialog to simplify support escalation.