Unable to install After Effects due to the error code 305

Hi,

All of a sudden I could not open AE CC2019 anymore. While opening it crashes.

I am running MacOs Catalina 10.15.3.

So I am trying to update to AE CC2020, but instead it gives a error code 305 during installing.

I also tried installing older versions, resulting in the same error code 305.

I have had no problems with installing and updating before.

The solution to this error code is: "try again". This does not help.

Can anybody help?

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