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Your LimeSurvey version: [Version 5.2.14+220214]
Own server or LimeSurvey hosting: Our institution is hosting LimeSurvey on its servers
Survey theme/template: Vanilla Theme
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The Gmail account holders have not received our email invitation. Others have confirmed receiving it, including Yahoo Mail and Outlook account holders. No error is shown and "OK" is displayed under "Email status". Any advice would be much appreciated. Thank you!

Alifbekov wrote:

No error is shown and "OK" is displayed under "Email status". Any advice would be much appreciated. Thank you!
 

There is no error to show. If the mail is accepted by the destination mailserver, there is no error to report for LimeSurvey.
What GMail andother mailprovider to with email (e.g. moving to spam, placing in quarantine or just deleting) is up them.

If a domainname is part of the emailcontent and that domain is an blacklist, you sometimes see vanishing emails without any report to sender or recipient that a mail has not reached the inbox.

I recommend to set a up a Gmail account and check, if invitations are landing i SPAM or are vanishing.
 

Hello Jelo,

Many thanks for your response. I have set up additional two Gmail and a Yahoo accounts and sent email invitations to these addresses. The Yahoo account has received the invitation but the two Gmail accounts did not. I am at my wits end and would be grateful for any direction.
Thank you.

We just realised that Hotmail accounts are also not receiving our invitations. Outlook, Yahoo are receiving them. Any guidance would be most appreciated. Thank you.

I don't think this is a Limesurvey issue. Limesurvey is obviously sending the emails, as the reach certain Email providers.

The issue is most probably with the server/method you are using for sending the emails out.

Sending mass emails is a science in itself and there are many things that can cause trouble. If specific email providers receive it and other don't, you are most probably on a black list, as Jelo suggests. No one really knows 100% what these big providers are doing in terms of that. However, what is strange is that Hotmail doesn't go through, but Outlook does. At the end it is both Microsoft.

Which type of email sending method are you using? PHP? SMTP? Sendmail? Qmail?

Hello Holch: Many thanks for your response. We are using PHP email setting. Any ideas how to resolve this? Thanks.

We are using PHP email setting.

You shouldn't. Usually this is not well configured and doesn't come from a good and trusted email server, so I am not surprised that many providers don't trust it. I would use a good and well configured SMTP server for sending out emails.

Many thanks! Much appreciated!