Fix Missing Emails in Spreadsheet

I have a customer list stored in a set of Excel worksheets that was compiled over time and, as a result, many email cells are empty. I need the file returned to me with those gaps intelligently filled so every record carries a valid, properly formatted email address.

Here is what I’m expecting:

• You will work directly in the Excel files I provide, review each row, research or validate the correct email address, and enter it without altering any other fields.
• Only missing-information cleanup is required; duplicate or formatting issues can be ignored for now.
• The finished workbook should come back with 100 % of the email column complete, plus a short “changes” sheet that notes any records you were genuinely unable to resolve and why (e.g., undeliverable domain, customer unreachable).

Familiarity with Excel functions, online lookup tools, and basic data-validation checks is essential so the returned addresses are accurate and ready for import into our CRM.