
Excel Pro Tips
How to Convert Old Excel Files to a New Format (2 Suitable Ways)
Learn how to convert old Excel files to a new format using Save As or VBA macros with simple, step-by-step instructions.
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3 articles tagged with “Excel File Extension”

Learn how to convert old Excel files to a new format using Save As or VBA macros with simple, step-by-step instructions.

Learn how to check an Excel file extension using File Explorer or directly within Excel to quickly identify formats like XLS, XLSX, and more.
![[Fixed] Cannot Open the File Because the Extension Is Not Valid](/_next/image/?url=https%3A%2F%2Fpub-b39c974f4c124a36a2fb517be38076ec.r2.dev%2Fimages%2F2026%2F08%2Ffeatured-image-excel-cannot-open-the-file-because-the-extension-is-not-valid-1780b661.webp&w=3840&q=75)
Fix 'Excel cannot open the file because the extension is not valid' by using Open and Repair, correcting extensions, Safe Mode, or settings.