Hello,

This error comes from the php_curl module. The module writes retrieved data from the web to a temporary file.

Here the plugin is simply querying Coingecko for some exchange rates. Since in this case the data is very small in size, this should not normally be a problem.

1. Check to see if the disk space on your web server is completely full. Only if the free space is 0 bytes this problem would arise. This could happen for example if you have left some logs running without logrotate.

2. Check to see that the wordpress directory and its subdirectories are writeable by the webserver (apache or nginx).

Depending on your system, you may need to do:

chown -R www-data:www-data /path/to/wordpress

But don’t just copy the command, check to see what the uid and gid should be, and check your system first. If you are not sure, take a full backup of your site first. This command can mess things up if you don’t know what you are doing.

In any one of these two cases, it is a misconfiguration of your web server. It is likely that this causes problems to more plugins than just this one. If someone else is administering your host for you, contact them about this.

Hope this helps.

Please let me know if you have any more questions.

with regards