Everyone who has not yet visited the website or doesn't accept cookies will see the dialog. If you use a subdomain to a real domain name it should not happen, but if you use a subdomain to a *.plesk.page domain, this will happen, too. It was a necessary tweak for the temporary domains, because...
Yes, but as the correct input field is not shown I suppose you are not a server admin, but a user in a subscription account. Only server admins can edit the PHP settings.
The php_value directive is only available if the vendor PHP version of the operating system is installed on the server. Else this directive cannot be used. Instead, enter the desired PHP settings into the "Additional directives" on the PHP configuration page.
This is a case for a deeper investigation by support. Please open a ticket with Plesk support so that an engineer can check the issue on your server for you.
To sign-in to support please go to https://support.plesk.com
If you experience login issues, please see this KB article...
From the information given, the most likely explanation is that the PHP version used is incompatible with the website scripts. As there are no further log entries available, this is the best guess I can do.
I think you are talking about this:
https://plesk.uservoice.com/forums/184549-feature-suggestions/suggestions/44893792-implement-support-of-spf-dmarc-and-dkim-anti-spam
You mentioned that you can login to the source with PuTTY, but did you try to SSH into your source server from the target server manually, so that you can verify that basically a root login from the target to source via SSH is possible?
Again, this here is the Plesk forum. We do not know who your provider is. You need to know that yourself. It's like you need to know in which street your house is. It's just nothing we can solve for you.
A single line of a log that only states that there is an internal server error when you open the website is not enough to determine the cause.
Is the website software compatible with the PHP version that you have selected?
Are there more lines logged to /logs/error_log or /logs/access_ssl_log...
I am sorry, but you need to know yourself where you are hosting your website. Normally, contact information is printed on your invoice, that you got from your provider, too.
No, please do not use PHP from Softaculous. You can choose the PHP version from Plesk and should only use that. Please use the Plesk GUI installer to install or remove PHP versions.
1. Connect to the server via SSH
2. Edit the following file on the target(Plesk) server:
/usr/local/psa/admin/plib/modules/panel-migrator/backend/lib/python/parallels/plesk/source/custom/actions/deploy_migrator_python.py
Append the (OSName.OS_CLOUDLINUX, '8'): 'PMM_0.1.11', line as...