Getting a cUrl 28 error code with REST Users API enabled

Thanks you for contacting me about this issue. I have had one other report of a similar conflict with the REST user API and a cURL call before but it turned out to be caused by another plugin that was making the cURL call to /wp-json/wp/v2/users/### and my firewall was blocking it. I never did get the full details from that other user so I would very much appreciate it if you are willing to work with me to narrow it down and let me know what you find.

As was hinted, at above the REST user API is referenced using the path /wp-json/wp/v2/users/ on your site, followed by a number which corresponds to a User ID in your database. My firewall rule simply blocks this URL on your site, so if this is causing a cURL error it would mean that there is something trying to access this URL on your site through a cURL call. I can help you to figure out what is causing it but I would need you to send me some more information first. Can you please send me a list of all the folders in your plugins directory and mark which ones are active or if any are inactive? Can you please also confirm which version of WordPress you have installed and what version of PHP your server is running?

Eli, thanks for the reply.
Below is the information you asked for and if you need anything else, let me know.
Looking at this list, I realize I have to do some reorganizing and drop some of these.

Active plugins

• Advanced Image Styles
• All-in-One Event Calendar by Time.ly
• Anti-Malware Security and Brute-Force Firewall
• Autoptimize
• Embed Code – Insert Header & Footer code
• Enhanced Text Widget
• Envira Gallery Lite
• Jetpack
• Page Builder by SiteOrigin
• Redirection
• Server IP & Memory Usage Display
• Simple Image Sizes
• Spacer
• WP Fastest Cache
• Yoast SEO

Inactive plugins

Duplicator

Current version of WordPress: 5.9.2

PHP Version: 7.4.19@64bitOS

Eli, hello. This is a follow up to my original support request above.

The situation seems to be resolved and I have reinstalled your plugin. I think the issue was with Jetpack and I think the issue with Jetpack was/is the overworked servers at AT&T hosting not timely communicating with Jetpack servers.

In addition to the cURL error, I was also, randomly, getting these messages from the Site Health Tool.

Deactivating the GOTMLS plugin ended the cURL error, mostly, but there were others:

1. The scheduled event, jetpack_sync_full_cron, failed to run. Your site still works, but this may indicate that scheduling posts or automated updates may not work as intended.

2. The REST API call gave the following unexpected result: (403)

3. The loopback request returned an unexpected http status code, 403, it was not possible to determine if this will prevent features from working as expected.

I was also getting occasional “cannot connect to database” messages. Those were fleeting and seemed to end by refreshing my screen. That makes me think the servers AT&T provides are overworked and underpowered.

Also, on the WordPress.com side, the site was not always syncing WordPress.com and occasionally. Sometimes I had to do it manually and even then sometime it was not communicating. I have never had that problem before.

Jetpack also started to prevent me from logging in to the admin area of the site after the last update, though the site was on the viewer end was functional. That was last straw time, and I deactivated and deleted the plugin.

Since then, it’s been running well, the error messages above stopped and I reactivated your plugin. Life is good again.

I am not going to pursue this with Jetpack support because for me the problem is resolved. Jetpack and AT&T Hosting don’t like each other.

To be fair to Jetpack, I use it a lot and have not had a problem with it, at least not a problem like this.

The GOTMLS plugin now seems to be functioning smoothly, no issues, and I am happy.

Thank you for posting this resolution. I have heard of Jetpack causing a lot of issues like this but it is so widely used that it ends up being a very small percentage of their users and it’s hard to replicate the issue or pinpoint the actual cause. There does seem to be something about certain servers that does not work well with Jetpack but I can’t get it to act up like this on any of my servers ??

Anyway, I’m glad to hear that you got it all worked out and my plugin is running smoothly for you now.