Vaadin update from 14.5.5 fails


Sorry, but this is a “how long is a piece of string” question, but maybe someone can point me in the right direction? I just don’t know where to start.

I finally managed to upgrade my Vaadin version to 14.5.5. This is fantastic news for me.

However, ANY Vaadin version after that (eg 14.6.9) builds and starts, but the browser only displays “Not Found”.

As a Swing developer who has ported a large product to Vaadin I still don’t know what is happing under the covers or how to debug.

Can anyone point give me ANY clues on what to fix or how to debug?

Any ideas would be HUGELY appreciated.


Hard to tell without more information like logs, used Frameworks and so on. First thing that comes to mind, would be a miss alignment between Vaadin Version and e.g. used Spring Boot version but really hard to tell without more context

Cheers. I didn’t set up the seed, so I’m not sure what else to add. It is not Spring Boot. It is actually embedded in to another java program (which is my backend). It was just strange that V14.5.5 works, and then V14.6.0 (or later) does not. I’m not sure what is “not found”. I guess that is the Undertow server expecting to find something at a certain spot … but it is not there. I fully realise this is a super vague question. Thx.

Also knoobie, thx for answering the last one re Flutter … after much work I got up to 14.5.5, and suddenly everything works nicely on iPhones / Safari, so no more need for Flutter. You saved me from certain death :slightly_smiling_face:

Giant leap for one man. Small step for mankind. Got past 14.6.0 and after a few tweaks all the way up to 14.9.8. Yikes. I’m up to date after 2 years. Undertow would not work from 14.6+. Solved by following clues in I barely understand what is happening, but happy to be up to date.