Sending Files That Won't Get You Fired
Practical advice for sending documents and images that look professional and actually open on the other end.
A colleague once sent a contract to a client as a .pages file. The client was on Windows. They couldn't open it.
The deal didn't fall through because of the file format. But the "can you resend that?" email wasn't a great look.
File sharing seems simple until it goes wrong. Here are the mistakes I've seen (and made) and how to avoid them.
The Universal Format Problem
You created something on your computer. It looks great on your computer. But the person you're sending it to has a different operating system, different software, different screen size.
Documents: Always send as PDF unless the recipient needs to edit the file. Word documents change formatting between versions. Google Docs links require permissions. PDFs look the same everywhere.
Images: JPEG and PNG work everywhere. WebP and HEIC do not. If you're sending photos from an iPhone, they might be in HEIC format by default — convert to JPEG first.
Spreadsheets: If the recipient needs the data, send CSV for simple tables or XLSX for complex ones. CSV works in everything. XLSX works in almost everything.
File Size: The Invisible Gatekeeper
Most email providers reject attachments over 25MB. Many corporate email systems cap at 10MB. Some at 5MB.
Your beautiful 30MB presentation? It bounced. And you might not even get a notification.
Before sending large files:
- Compress images inside the document. This alone usually fixes it.
- Remove unnecessary pages. That appendix with 15 reference screenshots probably isn't needed.
- Combine multiple files. Ten separate PDFs are harder to manage than one merged file.
If the file is still too large after compression, use a file sharing service instead of email. But compress it first anyway — nobody wants to download a 500MB file either.
Merge Before Sending
"Here are the files you requested" followed by 8 separate attachments is a headache for the recipient. They have to download each one, figure out the order, and keep track of all of them.
Take two extra minutes to merge related PDFs into a single file. Name it something descriptive. Attach one file instead of eight.
Naming Files Like a Professional
IMG_3847.jpg tells the recipient nothing.
Document1_final_v3_FINAL.pdf is worse.
Good file names are:
- Descriptive:
smith-contract-2026.pdf - Dated if relevant:
quarterly-report-2026-Q1.pdf - Versioned if needed:
proposal-v2.pdf(notproposal-new-newest.pdf) - No spaces: use hyphens or underscores (some systems handle spaces poorly)
Image Resolution: Match the Purpose
If someone needs an image for a presentation, 1200px wide is plenty. If they need it for print, they need the full resolution original.
Ask what it's for, then resize accordingly. Sending a 20MB raw photo when they needed a slide illustration wastes everyone's time and inbox space.
The Pre-Send Checklist
Before hitting send:
- ✅ Can they open it? PDF for docs, JPEG/PNG for images
- ✅ Is it under the size limit? Compress if needed
- ✅ Is it named clearly? Descriptive filename, no
final_final - ✅ Is it the right version? Double-check before attaching
- ✅ Did you open it yourself? Make sure it looks right
That last one catches more problems than you'd expect. I've sent PDFs with cut-off text, images with wrong crops, and once an Excel file with the "internal notes" tab still visible.
Nobody notices when files arrive correctly. But they definitely notice when they don't. A few minutes of preparation — right format, reasonable size, clear naming — is the difference between looking careless and looking competent.