I am delighted with Wordland – it makes it very easy to post to my various blogs. I encountered a problem uploading an image to one of my sites. I reported it here.

SOLUTION: This was a Jetpack problem. It turns out that I did have Jetpack installed, but the JSON API was not enabled.

Why was troubleshooting this so hard? There were a couple confounding factors:

• It's an atypical configuration – Jetpack was installed but without (today's) default use of the JSON API. This site – RandomNeuronsFiring.com – has been continually updated since, I think, 2013. I am unsure when I first installed Jetpack, but it could well have been before the JSON API arrived, so perhaps it was never turned on by default. Enabling the JSON API made images work flawlessly.
• Posting text worked fine (see recent posts on this site). It was confusing when posting images to my blog did not work.
• Posting images to another (more recently created) blog worked fine. Since it's a newer installation, I assume that the Jetpack defaulted the JSON API to be enabled when this site was created.

I found the answer by searching some of the other Issues, and saw someone mention Jetpack settings. I then checked the Docs and noticed the Jetpack JSON API requirement.

I hope the following advice – a) ensure Jetpack is installed; b) ensure the JSON API is turned on – can make it into a Troubleshooting section of the documentation in the future.

Update: I am not really sure what I did to "enable the JSON API" in my WordPress site that made it work. I went back to the site, checked the Jetpack -> Settings, and clicked the "Modules" link at the bottom. This shows a whole list of modules, and JSON API was active. I clicked Deactivate, and, sure enough, I was unable to make edits – I saw an appropriate error message. Re-activating it left it working fine.