October 5, 2026
Why the same vertical video can publish on one platform and fail on another
A file can be accepted by one platform and rejected by another because publishing depends on more than aspect ratio: file limits, account eligibility, permissions and metadata all matter.
“It is a vertical MP4” is not enough to guarantee that a video will publish everywhere. Each platform validates a different combination of the media file, the target account, the publishing app and the post settings.
1. The media file
Platforms can differ on duration, file size, resolution, frame rate, codecs and containers. A file can therefore be valid for one destination and outside the accepted envelope for another.
2. The account
Some publishing features depend on the account type or destination. Instagram API publishing, for example, is built around eligible professional accounts. Facebook publishing targets a Page rather than a personal profile.
3. API access and review
Platforms may restrict what an application can do until it passes review. TikTok documents that unaudited Direct Post clients are restricted to private posting. YouTube similarly restricts uploads from certain unverified API projects to private viewing until an audit is completed.
4. Post settings
Privacy, comments, branded-content disclosures, AI labels and other settings are not identical across platforms. A value that exists on one network may not exist on another, or may depend on the target account.
A better workflow
Validate first, publish second. Inktaro checks each selected destination before scheduling and keeps a separate status for each platform. If one destination fails, the others do not need to be republished.
Official references: TikTok Direct Post API and YouTube videos.insert.