After upgrading to Matomo 3.14 I am facing several issues:
When upgrading, I ran into an error saying the following:
Entry “DeviceDetector\Cache\Cache” cannot be resolved: the class is not instantiable. Full definition: Object ( class = #NOT INSTANTIABLE# DeviceDetector\Cache\Cache scope = singleton lazy = false )<<
I was searching for solution. They were:
- update DOMAIN/matomo/config/global.php manually
- rename DOMAIN/matomo/config/config.ini.php
This did not solve the issue, and so I reinstalled Matomo from scratch. This seemed to work. But now I found the error when I refresh my Matomo page: “SQLSTATE[HY000] [1040] Too many connections category”
I’ve had a look into this discussion: :(Upgrading from 1.6 to 1.7 after Too many connections - Yes, this is old and has nothing to do with Matomo 3.14. The solution was a patch. What may be the solution for the new occurance?
Strange behavior, because the error does not occur always. And sometimes I receive a red message in Matomo Dashboard, saying “Oooops, something went wrong, please contact your Matomo administrator” or similar.
I was always satisfied with Matomo. It always gave me a good overview and the possibility of deeper analysis. But the UX decreased with Matomo 3.14. 
Thanks and have a nice day.
Henning
6 posts - 2 participants