Media and attachment problems
WhatsApp enforces file size limits: images, video and audio up to 16 MB, documents up to 100 MB. A file over the limit will not send. The other common cause is a file that was moved, renamed or deleted after the template was created — templates reference the file, so breaking the path breaks the send.
File size limits
These are WhatsApp's limits, not BuzzRelay's, and they cannot be raised:
| Type | Maximum size |
|---|---|
| Image | 16 MB |
| Video | 16 MB |
| Audio | 16 MB |
| Document | 100 MB |
A file over the limit fails to send. Resize or re-export it:
- Images — export at a lower quality or smaller dimensions. A photo for a phone screen rarely needs more than 1–2 MB.
- Video — 16 MB is restrictive. Keep clips short, or host the video and send a link instead.
- Documents — a PDF over 100 MB usually has uncompressed images inside; re-export at a lower resolution.
Smaller is better than merely legal. A 15 MB video technically sends, but it downloads slowly on mobile data and many recipients never open it. Aim well under the limit.
The file cannot be found
Templates reference the media file. If it moves, the reference breaks.
This bites when:
- The original was on a USB drive or network share that is no longer connected.
- The file was renamed or deleted after the template was created.
- The template came from another computer where the path was different.
Fix by editing the template and re-attaching the file. Uploaded media is kept in %APPDATA%\BuzzRelay\media\, which is why that folder matters in a backup — see Where BuzzRelay stores your data.
Only media messages fail, text is fine
If a mixed campaign sends text but not attachments, work through:
- Size — check against the table above.
- The file exists — open it from Explorer to confirm.
- Format — unusual containers can be rejected even under the size limit. MP4 for video, JPG or PNG for images, PDF for documents are the safe choices.
- The file is not locked — a PDF open in another program can fail to attach.
- Slow connection — large uploads on a weak connection can time out. A smaller file usually resolves it.
Media sends but arrives broken
| Symptom | Cause |
|---|---|
| Image arrives heavily compressed | WhatsApp recompresses images. Send as a document to preserve quality. |
| Video will not play on some phones | Codec compatibility. Re-encode as H.264 MP4. |
| Document arrives with a different name | The original filename travels with the file — name it sensibly before attaching. |
| Audio arrives as a file, not a voice note | Expected. Attached audio is not the same as a recorded voice message. |
Campaigns with media run slower
Each attachment has to upload before the message sends, so a campaign with a 5 MB image takes noticeably longer per recipient than a text-only one. That is on top of your configured delays.
If timing matters, work out the real duration before scheduling — a media campaign to a few hundred recipients can run for hours, and pushing into the night is a genuine ban risk. See Best time to send WhatsApp marketing messages.
Test media with a real send. The preview shows the message, not what WhatsApp does to the file. Send a one-recipient campaign to your own number and open it on your phone.
Frequently asked questions
What are the WhatsApp file size limits?
Images, video and audio up to 16 MB, and documents up to 100 MB. These are WhatsApp's limits rather than BuzzRelay's and cannot be raised — a file over the limit will not send.
Why does my image or video fail to send?
Most often the file is over WhatsApp's size limit, or it was moved, renamed or deleted after the template was created so the reference no longer resolves. Check the size first, then confirm the file still exists at its original location.
Why do my images arrive blurry?
WhatsApp recompresses images it sends as photos. To preserve quality, attach the image as a document instead, which is delivered without recompression.
Do campaigns with attachments take longer?
Yes. Each file has to upload before the message sends, on top of your configured delays. A media campaign to a few hundred recipients can run for hours, so allow for that when scheduling.
Last updated: