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Your LimeSurvey version: LimeSurvey Community Edition Version 6.1.6+230703
Own server or LimeSurvey hosting: Own Server (2mhost.com)
Survey theme/template:
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I have tried Office 365 and GMail - none of them seem to work with SMTP. I tried editing the email.php file directly and that didn't work either. I've looked at all available support pages and there are very little answers if any out here on SMTP working with this edition of LS. I'm just about ready to give up and move to Alchemer. Any suggestions? Is anyone else in this same situation and coming up short on answers?

There is a huge number of discussions about how to make Office 365 or Gmail work with Limesurvey.

In Gmail you will need to allow Limesurvey to be one of the webapps that can send email. But keep an eye on the limits for mass emailing with Gmail.

Office 365 has also some pitfalls (mainly because they do things different, like always), but people have managed to make it work.

I personally wouldn't want to use Office 365 or Gmail for sending mass emails in general anyway, but would rather use a good SMTP server that is made for this. But this is of course personal preference. Sending mass emails is a science in itself and things can get wrong. I wouldn't want my business email being blocked, because of a small mistake when sending an email invitation and suddenly all major email providers blacklist your business email. there is so much that can go wrong.

I have tried Office 365 and GMail - none of them seem to work with SMTP.

What exactly does "none of them seem to work"? Either they work or they don't. What is the issue? What happens when you try to send emails? Did you switch on the debug mode for email? Any error messages?

But I highly recommend to do some search here in the forum, many could solve their issues sending emails via Office 365 and Gmail here in the forum in the past.

Maybe this link for Office 365 helps you. I don't use Office 365 for email in my organization, so I can't give any details.

learn.microsoft.com/en-us/exchange/mail-...ft-365-or-office-365

Yes, I am aware of all the discussions. None seem to hit on my issue.

I can't tell what is going on when I send an email because I can't find the SMTP debug location. I'd like to use a separate SMTP server/service for the reasons you cite here BUT it looks like none of the email options are working at all in my LimeSurvey installation. Let's assume for a minute that it's not GMail or Office that is the issue. How in the world do I troubleshoot when I can't see any debug logs?

Side note - I tried editing email.php directly and still nothing, and I noticed the email UI didn't match what's in the PHP page.

Keep your hands from "email.php" for now. This should not be necessary. Sending emails works for others, so the problem must be somewhere else. Hacking the code is always the very last approach and I am quite sure that it won't be necessary here.

What do you mean with "I can't find the SMTP debug location"?

Did you go to "Global settings" --> "Email settings" --> "SMTP debug mode:" --> Always?

Afaik, on trying to send emails you should receive some notifications if things go wrong.

Debug is on Always.

I am going to register another domain and use the simple mail that my hosting provider uses to try and ferret this out...if I can't get a simple bare-bones SMTP email to work I know it's LimeSurvey and not the provider.

We can't exclude that there is an issue with Limesurvey, but my experience is that in these cases it is some kind of weird setting or restriction on the email provider side.

Many users get it to work on a daily basis and the SaaS service of the Limesurvey GmbH also offers Limesurvey on their servers with email. So email in general is working.

Of course there can always be a bug that only affects certain installations, so we can't rule this out completely.

Let's see if one of the experts in terms of Email settings (like Jelo or Denis) have other ideas as well.

So, I quickly set up a simple email on a new domain I just purchased and I get the same issue. Nothing at all from LS. No errors. It acts like it worked but I see no emails either coming or going. Something in the installation is wrong.

OK, can you post what your settings look like?

Of course hide the actual information, just to see the general settings and what you put where.

Something in the installation is wrong.

If you did a complete new installation I don't think it has to do with your specific installation either. Because it would be weird if twice things go wrong during installation the same weird way.

Are both the same LS 6.1.6+230703? Did you set the new one up from scratch? Or did you copy it from the first one?

I will try to setup the email feature on my test installation of LS 6 here to see what happens.

With which type of emails are you currently trying? (e.g. Survey invitations, user notifications like email to new users, test email feature)?

here are a few reasons why Office 365 and Gmail might not be working with SMTP. Here are some possible causes and solutions:

Incorrect SMTP settings. Make sure that you have entered the correct SMTP server name, port, and encryption method for your Office 365 or Gmail account. You can find these settings in the account settings for your email client.
Two-factor authentication. If you have two-factor authentication enabled for your Office 365 or Gmail account, you will need to create an application-specific password to use with SMTP. You can create an application-specific password in the security settings for your account.
Server outage. There may be a temporary outage on the SMTP server for Office 365 or Gmail. If you are sure that your SMTP settings are correct, try again later.
Firewall or proxy settings. If you are using a firewall or proxy server, it may be blocking SMTP traffic. You will need to configure your firewall or proxy server to allow SMTP traffic for Office 365 or Gmail.
If you have tried all of these solutions and you are still having problems, you can contact the support team for Office 365 or Gmail for help.