Gmail SMTP plugin not working on 1&1 hosting

I’ve just migrated a WordPress 5.6 website from my development IIS server to 1&1 hosting. The Gmail SMTP plugin works fine on my development server but fails when sending test emails on 1&1. The error that’s returned after about 2-3 minutes is:

The page you are looking for is temporarily unavailable.
Please try again later.
3ff5ff9f5c64c02c6670a298faf37d7e dc370a1da1aae5449eefb6707f02cf57 0d0f4fdd2c0415561e1e4c05d6dc95c3

The normal status screen when sending a test email doesn’t appear at all. I used the “All-in-One WP Migration” plugin to migrate the website and everything else appears to be working on the site.

The URL *did* change between my dev server and 1&1 hosting – it went from http://www.bollingtonbeerfestival.co.uk to just http://bollingtonbeerfestival.co.uk which I guess is a 1&1 default. As this URL is used as a setting in the GMail SMTP plugin, I created a new set of Google credentials, revoked access and granted it back. All that works fine.

This is the server info on 1&1:

OS: Linux info 3.0 #1337 SMP Tue Jan 01 00:00:00 CEST 2000 all GNU/Linux
PHP version: 5.6.34
WordPress version: 4.9.5
WordPress multisite: No
openssl: Available
allow_url_fopen: Enabled
stream_socket_client: Available
fsockopen: Available
cURL: Available
cURL Version: 7.38.0, OpenSSL/1.0.1t

This it the server info on my dev server:

OS: Windows NT RIVENDELL 6.3 build 9600 (Windows Server 2012 R2 Standard Edition) AMD64
PHP version: 5.6.35
WordPress version: 4.9.5
WordPress multisite: No
openssl: Available
allow_url_fopen: Enabled
stream_socket_client: Available
fsockopen: Available
cURL: Available
cURL Version: 7.59.0, OpenSSL/1.0.2o

Slightly newer version of PHP on my dev server and newer versions of Curl & OpenSSL. Connected?

Any ideas as I’m stumped?

• This topic was modified 8 years, 1 month ago by robnicholson. Reason: HTTP prefix

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