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Dimitri Van LooyDimitri Van Looy 

Uncaught TypeError: Cannot read property 'b' of null throws at

Today my Lightning sandbox is having some serious behavious issues. 
I run into following errors:
  • Unfortunately, there was a problem. Please try again. If the problem continues, get in touch with your administrator with the error ID shown here and any other related details. An internal server error has occurred Error ID: 1986783592-9485 (1990134024)
  • Uncaught TypeError: Cannot read property 'b' of null throws at
When I refresh the window, the error disappears and I can continue working untill the next one appears, and so on.

Anyone have any clue what is happening? 

Did you ever get this figured out? If not, I can look into it and try to help you out.

Greg Thomson
Dimitri Van LooyDimitri Van Looy
Hi Greg,
Untill now I did not get any reasonable explanation on what happened. But the errors disappeared few days later. I assume it had/has something to do with Spring'17 rollout and bugfixing.

Thanks anyway for your offered assistance, highly appreciated!
Julian Olsen 2Julian Olsen 2

we do have the same problem in a production environment. Any idea where this comes from? 

Thank you and regards
Stijn Zeebroek 14Stijn Zeebroek 14
Same problem here in production...
same issue here today
Michael PlunkettMichael Plunkett
We've gotten this error message numerous time in production on Spring '17 -- have not been able to narrow down a cause.
Benjie CruzBenjie Cruz
We're getting the same issue. Any solution for this?
Paul JuneauPaul Juneau
I am getting the error as well in my Sandbox.  This has been happening ever since I made my own custom app.  I cannot dismiss the message and attempt to resolve.
 Uncaught error in sandbox
J EllosoJ Elloso
I do have this:

You can click on "This Issue Affects Me" for updates 
Jennifer HarendaJennifer Harenda
Got this error in a partial sandbox after making a few very minor configuration changes to the Lightening Sales app, quite curious about what might be going on. 
Helen RussellHelen Russell
Getting this issue in Production: eu11. Refreshing seems to fix it, but it's annoying when it crops up. Any news?
Nikita Jain 44Nikita Jain 44
Hi,any solution for the below given error:
Uncaught TypeError: Cannot read property 'b' of null throws at