After uploading all the files again, the error message is gone. Contact form still doesn't work! :(
# Office365

Try latest update 2019.1.5

then do a full upload.

Still don't work.

v2019.1.6

Good day to you Bjorn

I would like to inform you that the issue has been addressed in the latest 2019.1.6

It seems to have been generated by a faulty installer prior to the 2019.1 release that didn't correctly overwrite older files.

Please update your software and try this again. Give me a feedback here if possible

Thank you

Stefano

As I said, I'm using v2019.1.6 and I still have the same problem.

Setting.

E-commerce doesn't work either. No e-mail is sent to either the customer or the supplier (me).

As always, support from X5 is absolutely miserable.
Everything worked as it should before updating, but after updating you get problems and no help.
You do not take your customers seriously.

Bjorn, could you check your website host is using at least php v5.6 (or the recommended php7.1)

Hi Bjorn

Unfortunately, it seems like the issue which other users were experiencing has nothing to do with your case specifically.

The issue only touched those who were using the PHPMailer script type, which is not your case ( since you're using SMTP ) 

Error 500 indicates a server issue, for which the server hosting should have an official LOG on their servers indicating exactly what seems to be the issue. If possible, please ask them to provide this information to you and attach it here, so that I might dig into this issue faster for you.

For the moment, no report of issues with the SMTP has been received from any user. Perhaps something changed with the SMTP credentials on your hosting? What if you attempt to perform the mailing tests at /admin.

Does it work there?

Please verify all of this and keep me posted on the result

Thank you

Stefano

Admin and error:

[2019-04-09 09:52:51] SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting

Sorry. My mistake!