Hook custom validation error

Hi again Team,
I'm trying to hook custom login validation error. I managed to throw it as new Exception message and it show's on the lower left corner. Can I hook/throw this same error on the login validation (the one with red background wrapped with div.Messages Errors > ul > li)?
I've search hours on this forum, can't find any.
TIA
0
Comments
Hard to tell without any code from you.
Look at this code, taken from the EntryController:
Instead of throwing an error, I would simply "put" it there.
Thanks again @R_J , I indeed managed to add custom error using the condition on $sender->Form->formValues().
You rock!