Duplicati2 is not backing up any more after upfate

duplicati made the last successful backup on April the 22nd. sibce then I got errors when trying to start a new back-up run.
The strange thing is, that on the 23 of April duplicaty updated on “Duplicati - 2.0.3.6_canary_2018-04-23” which is according to duplicati.com not the latest version, which is 2.0.3.3.
could it bee that somehow I got a testing version installed and this is causing the problems?

By the way, if I am trying to check the logins the latest entry is from May the 19th, but there no errors are reported.

What errors are you getting?

It looks as if you have the latest “Canary” version installed. Unlike most canary versions, the 4-23 version is allegedly not very stable unfortunately. What is your “update channel” set to in Settings? If you don’t want canary versions, you should verify that this setting is set to something else, preferably “Beta”.

What errors are you getting?

I think it is the following:
System.AggregateException: Unexpected difference in fileset 57, found 130581 entries, but expected 139863 —> System.Exception: Unexpected difference in fileset 57, found 130581 entries, but expected 139863

It looks as if you have the latest “Canary” version installed. Unlike most canary versions, the 4-23 version is allegedly not very stable unfortunately. What is your “update channel” set to in Settings? If you don’t want canary versions, you should verify that this setting is set to something else, preferably “Beta”.

How can I change the instaled version. Just changing the settings does not help, even if I do a new install I am ending up with the 4-23 version?

This is a known issue that I had as well, seems the new multi-processor setup in 2.0.3.6 is having problems if more than one CPU is processing the same set of files. You have 4+ CPUs processing files so they all report in how many they expect as a whole, but individually they are processing their own batch so it is only claiming it found a different number.
For now it is best to go back to 2.0.3.5, and after that is setup, do not click the “update now” messages.