"This File Won't Open" — .docx, .pages, .odt & Other Mystery Attachments
Last verified: October 2026
The little letters after a file's name tell you what it is and how to open it — free. Decode .docx, .pages, .odt and the rest, safely. Rather have a hand? My number is (330) 200-8042.
Decoding a Mystery File, at a Glance
Someone emails a file and it won't open, or your computer asks what to use. The little letters after the dot — the 'extension' — are the clue: .docx is Word, .xlsx is Excel, .pdf is a PDF, .pages is Apple's word processor, .odt comes from free office programs. Most open free in the web versions of Office or Google, or in LibreOffice; Apple files open at iCloud.com or you can just ask for a PDF. But first, the safety rule: never open an attachment you didn't expect without checking with the sender. This guide decodes it all, and there's a printable 29-page version up top.
Common Questions
1 Why won't this file open on my computer?
Usually because you don't have the program that made it — not because it's broken. The ending after the dot tells you the type, and a free opener (web Office, Google Docs, or LibreOffice) can almost always handle it.
2 What do the letters after the dot mean?
They're the file type: .docx is Word, .xlsx is Excel, .pdf is a PDF, .pages is Apple's word processor, .odt is from free office programs. They tell you which program opens it.
3 How do I open an Apple .pages or .numbers file on Windows?
Open it free at iCloud.com with an Apple account, or simply ask the sender to re-send it as a PDF or Word file, which opens anywhere.
4 What opens an .odt file?
Free LibreOffice opens it natively, and modern Word and Google Docs usually can too. It's a standard open-document format — nothing exotic.
5 Is it safe to open any attachment?
No. Verify you expected it and that it's really from the sender first. Be wary of program endings like .exe, double endings like '.pdf.exe', and 'enable content' prompts.
6 What's the easiest fix when I'm stuck?
Reply and ask for a PDF. A PDF opens on every device, so it's almost always the simplest answer to a 'won't open' file.
Would You Rather I Just Help?
Mystery attachments are quick to sort out once you know the trick — and I'll keep you safe while we do it. I'll set you up with free openers, turn on file extensions so you can see what's what, and show you how to spot a bad one. $99 flat for a visit, or $49 on-screen, 30-day come-back-free.
Would you rather I just do this for you?
No shame in it — plenty of folks would rather hand it off, and that's what I'm here for. I'll come to your home, set it up right, and make sure it's working before I leave. Flat $99 per visit — no jargon, no upsell, and every visit is 30-day come-back-free.
Not a hardware job? I can often fix it remotely for $49 — a secure screen-share, up to 2 hours, that you watch the whole time and can end whenever (included free for $39/mo Support Plan members, and it counts toward the $99 if it turns out I need to come out).