If you cannot open an Excel file and see Excel cannot open the file because the file format or extension is not valid error, see this post.

If Microsoft Excel opens a Blank screen when you open an existing file, then you can stop Excel from opening a Blank workbook or sheet.

Microsoft has announced that it will start disabling external workbook links to blocked file types by default between October 2025 and July 2026.

Fill Blank Cells in Excel Using Dynamic Array Functions Watch this video on YouTube. Expand your understanding of Excel functions with additional resources from our extensive library of articles.

Microsoft doesn't recommend re-enabling refreshing external links to blocked file types: "Disabling these protections reduces security and should only be done with caution." ...

When you're reformatting a drive, memory card, or flash drive you need to pick a file format. If you see FAT32, exFAT, and NTFS, but don't know which one to pick, here's what you need to know.