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Trigger failure causes login flow exception. Problem is that I have only one admin user in this development sandbox. Other user has standard user profile and it can be logged in. This other user doesnt have capabilities to deactivate login flow or deactivate trigger causing this error.

I have tried to reset password and it failed too because login flow was activated even in password change.  Is there way to get access back without dumping sandbox and rebuild it from a scratch? Force IDE is not a option because security token is not valid. All help I can get is much appreciated, thanks!