c# - Sequence contains no elements server side -


i developing asp.net mvc web application , have been deploying web server few months now. have experienced new error confused me. upon publishing application, , loading website, following error message:

 sequence contains no elements   description: unhandled exception occurred during execution of current web request. please review stack trace more information error , originated in code.    exception details: system.invalidoperationexception: sequence contains no elements   source error:   unhandled exception generated during execution of current web request. information regarding origin , location of exception can identified using exception stack trace below.  stack trace:    [invalidoperationexception: sequence contains no elements]  system.linq.enumerable.first(ienumerable`1 source) +514 system.linq.queryable.first(iqueryable`1 source) +330 labsys.mvcapplication.application_authorizerequest(object sender, eventargs   e) +1261   system.web.synceventexecutionstep.system.web.httpapplication.iexecutionstep.execute() +92  system.web.httpapplication.executestep(iexecutionstep step, boolean&completedsynchronously) +165

i confused, because application runs on localhost, without issue or error message. checked database, , connected , validated server. there should no error.

thanks in advance!

check in code make sure firstordefault() or singleordefault() used instead of using of these: first() or single().

when thelinq error "sequence contains no elements", because using first() or single() command rather firstordefault() , singleordefault().

sequence contains no elements?


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