error 500 how to diagnostic ?

[recifbox]

i have recently upgraded and begin to push online module from 4.0 converted ... at a moment of time i get this:

 

how i can dig the error ?

 

the only thing i get in my dashboard is : 

 

 

when i check manually i get this :

 

 

anny idea ?

[recifbox]

any idea about how to resolve this ?

 

i have spoted this on bug tracking : https://community.invisionpower.com/4bugtrack/active-reports/40121-underflowexception-r7416/

[Daniel F]

https://community.invisionpower.com/4docs/knowledgebase/40121-updatecheck-error-r169/ :)

[recifbox]

And the man of the day is Daniel F ( i can continue my journey to migrate my stuff to 4.0)

and the winner is : 

 

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(not yet updated to 4.0)

 

in fact i have all this apps not yet updated (need to find them or need to wait dev) and i didn't want to removve them to avoid data lose associated to them, but my home page stay in error 500, next step is how to make work the home anyway ?

(apps not updated)

 

[recifbox]

anny idea to fix  this step (i didn't want to delete apps)

[recifbox]

bump of the day to get a hand on this ?