For a few days I'm unable to install new plugins because I get an err_response_http_code 403 within two Moodle instances both running on the same hosted server.
The involved Moodle version are:
- Moodle 3.1.10 (Build: 20180115) uses https access
many Plugins regulary updated - Moodle 3.1.8 (Build: 20170911) uses http access
using nearly no additional plugins, rarely updated
Following the link https://moodle.org/mod/forum/discuss.php?d=352095 I tried to install the certificate in question into the moodledata folder, but it didn't solve the problem.
When I try to install the plugin via Moodle server I get the following error:
There is a request to install plugin Buttons (format_buttons) version 2018022400 from the Moodle plugins directory on this site. However, the plugin installation pre-check failed (reason code: remoteunavailable).
Installing plugins via ZIP file still works.
As far as I understand the problem is caused by a communication error between the hosted server and the Moodle server.
Any ideas what to try next are welcome.