Direct answer
Make a copy, keep every original column and a unique row ID, then join verification statuses back to the original file. Delete or suppress rows using the status column, not a one-column export.
More questions and answers
Why does my email CSV have blank rows?
Filter out fully empty rows while retaining partially completed contact records for review. Blank names do not necessarily mean the email address itself is invalid.
How do I clean an email CSV with two email columns?
Choose the primary address column for verification, then inspect secondary addresses separately. Avoid verifying a phone or backup-address column accidentally.
My CSV has semicolons instead of commas. Can it be cleaned?
Import the file using the correct delimiter and check whether addresses landed in separate cells. Re-export to a standard CSV before verification if the tool expects commas.
Why do addresses disappear when I open a CSV in Excel?
Excel may guess delimiters, encodings or data types. Import through its text/CSV import flow, inspect a sample, and preserve the original raw file.
How do I clean emails pasted from a PDF?
Extract candidate addresses, remove spaces introduced by line wrapping, and inspect suspicious joins manually. Then verify the resulting list instead of assuming that text extraction was accurate.
How do I remove weird spaces from email addresses?
Trim whitespace, including nonbreaking spaces and hidden characters, while preserving a copy of the original value. Recheck the address syntax after cleanup.
Can I clean a UTF-8 CSV containing accented names?
Yes, but preserve UTF-8 encoding and original names. Address verification and the formatting of display names are separate jobs; do not strip accents from people's names as a cleaning shortcut.
How do I clean an email CSV without changing the order?
Add a row-number column before processing, keep it through the export and sort by that value afterwards. Make sure the verifier or import tool preserves the row ID.