File Format Mismatches
Not all "CSV" files are created equal. Some systems export files with semicolons, tabs, or pipes instead of commas as delimiters.
Common delimiter variations::
- Comma: `John,Doe,28`
- Semicolon: `John;Doe;28`
- Tab: `John Doe 28`
- Pipe: `John|Doe|28`
When you try to import a semicolon-separated file into a system expecting commas, each row gets treated as a single giant field. The import usually fails with "wrong number of columns" or similar errors.
Before importing, always check what delimiter your target system expects and verify your file uses the same one.
Data Validation Failures
Import systems enforce data rules—when your CSV breaks those rules, the import fails.
Common validation failures::
Required fields are empty:: - Your CSV has blank cells in columns the system requires
Data type mismatches:: - Text in a number field, invalid dates
Value too long:: - Field exceeds maximum character limit
Invalid format:: - Email addresses without @, phone numbers with letters
Constraint violations:: - Duplicate values in fields that must be unique
Most systems give cryptic error messages like "validation failed on row 47" without explaining why. You have to manually inspect that row to find the issue.
The best approach is cleaning and validating your CSV before attempting import.
Row Limit Exceeded
Many import tools restrict how many rows you can import at once. This is especially common with:
- SaaS platforms on free or starter plans - Database admin panels - Email marketing platforms - E-commerce product import tools
Example limits::
- Shopify: 50,000 products per import
- Mailchimp: 25,000 contacts (varies by plan)
- WordPress: Often 1,000-5,000 items depending on hosting
If your CSV has too many rows, the import gets rejected entirely. You'll need to either upgrade your plan or split the file into smaller chunks.
Encoding and Special Characters
CSV files can be saved in different character encodings. If the import system expects UTF-8 but your file is in ISO-8859-1 or Windows-1252, special characters break.
What goes wrong::
- Names like "José" or "François" display as gibberish
- Currency symbols (£, €, ¥) render incorrectly
- Emoji and special characters cause crashes
- The entire import may fail if the system can't parse the file
This is particularly common when exporting from Excel on Windows, which often uses Windows-1252 encoding instead of UTF-8.
Solution:: Save your CSV as UTF-8 in your spreadsheet app before importing, or use a text editor to convert the encoding.
Headers Don't Match Expected Fields
Import systems often map CSV columns to database fields by matching header names. If your headers don't match exactly, the import fails.
Common header problems::
Case sensitivity:: - `email` vs `Email` vs `EMAIL`
Extra spaces:: - `"Customer Name"` vs `"Customer Name "`
Different naming:: - Your CSV has `"Full Name"` but system expects `"Name"`
Some systems let you manually map mismatched headers, but others require exact matches. Always check the import documentation for the exact field names required.
Ready to put this into practice?
Use our free CSV cleaning tools to fix these issues automatically: