We are using Matomo (ex Piwik) since years without problem. But now there are problems:
E-Mail reports generated once a month are empty now, reporting 0 to 3 visitors, but my dashboard shows thousands of them. So tracking works, reporting not.
E-Mail reports generated by hand as admin do not work any longer, there is for half a second shown:
“Failed to load HTML file: Please check if you have an ad blocker or something similar enabled.” I do not have an ad blocker active.
Matomo is the actual version, I just updated it again manually, no change. So at the moment it is out of order and I cannot figure out why.
Problem still existing. There is no usable error report.
When I click on “Download”, every report is fine, it is generated and shown correctly.
When I click on “Send report”, Matomo is working, but no report is generated or sent; the same happens when the monthly report should be created and send via cron.
Found it!
Matomo is sending mails in non-UTF8, the MTA postfix only accepted SMTPUTF8 and rejected the mails. After changing postfix to accept non-UTF8-mails, everything is fine.
I do not know how to configure Matomo to send SMTPUTF8-mails.