How to Fix Microsoft Lists Import Type Errors

“Some data couldn’t be imported” means Microsoft Lists created or previewed the structure but rejected rows containing values that do not match the assigned column type, or a person who cannot be found in the address book. Fix the source data and type mapping before repeatedly uploading the same file.

Why Microsoft Lists Skips Rows During Import

A visually formatted Excel column can still contain mixed underlying values: numbers stored as text, formulas returning blanks, inconsistent dates, extra spaces, or identifiers with leading zeros. Person columns add another requirement—the value must resolve to a valid directory user.

Prepare and Import a Clean Excel or CSV Table

1. Copy the source. Work on a duplicate so cleanup does not alter the only business record. Remove merged cells, subtotal rows, decorative titles, and completely blank rows from the import range.
2. Create one Excel table. Select the data, choose Home > Format as Table, confirm that the first row contains unique headers, and give every column a meaningful name.
3. Normalize each column. Use real dates in date columns, numbers only in numeric columns, one consistent value set for choices, and plain values instead of formulas that return errors. Trim leading and trailing spaces.
4. Start the import. In Microsoft 365, open Lists > New list > From Excel or From CSV, choose the file and table, and review the proposed type for every column.
5. Use text for uncertain fields. Map mixed identifiers, phone numbers, postal codes, or inconsistent data to Single line of text first. Create stricter list columns only after the source is clean.
6. Verify the result. Open the skipped-row details, compare source and imported row counts, and test sorting or filtering for each important column.

Resolve Person, Date, Number, and Choice Columns

• Person: use valid organizational email addresses and verify each one can be selected in Microsoft 365.
• Date and time: replace ambiguous text dates with real spreadsheet dates and keep one consistent interpretation.
• Number: remove currency symbols and explanatory text; keep IDs as text when leading zeros matter.
• Choice: standardize spelling, capitalization, and spaces before converting the destination to a Choice column.
• Reserved names: rename ambiguous headers such as ID or Type if they conflict with existing SharePoint fields.

Use WPS Spreadsheets to Clean the Source File

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WPS Office cannot change Microsoft Lists permissions or directory records, but WPS Spreadsheets can directly prepare the XLSX or CSV source before it is uploaded again.

Open a copied file in WPS Spreadsheets, remove merged rows, trim spaces, convert formulas to verified values, standardize dates and numbers, then save as XLSX or UTF-8 CSV. Reopen the saved file and confirm headers, delimiters, leading zeros, and row count before uploading it to Microsoft Lists.

Microsoft Lists Import FAQs

Why does Microsoft Lists say that some data could not be imported?

At least one value does not match the column type selected during import, or a Person value cannot be resolved in the organization directory. Inspect the omitted row numbers and compare each value with its destination type.

Should I import mixed columns as text first?

Yes, when a column contains mixed values or identifiers with leading zeros, map it to Single line of text during list creation. After verifying the import, create a correctly typed destination column and convert the values deliberately.

How should email addresses be prepared for a Person column?

Use one valid work or school address per cell and confirm that each person exists in the organization address book and can be selected manually in Microsoft 365. External or inactive accounts may not resolve.

How many Excel rows can Microsoft Lists import when creating a list?

Microsoft’s list-from-spreadsheet guidance supports tables with up to 5,000 rows. For a large file, test a small representative table first so type or permission errors are easier to isolate.