Email stuck in Outbox - Microsoft Community

i had outlook, part of office 365 home,  configured receive emails gmail account, , had worked fine years until yesterday when tried sending email gmail account had sent usual exchange account. had received message saying that email not delivered. got message "microsoft outlook has stopped working" , program re-start automatically. upon restarting, same message, time program close , windows notify me if solution available. 

the size of email in outbox 140 kb--not big.

i can outlook work again starting in safe mode , deleting gmail account. however, email trying send still in outbox , not able delete it.

i've tried setting outlook work offline , restarting (restarting several times), still can't delete email in outbox. message telling me outlook has started transmitting message.

i've added gmail account again. outlook tells me account has been set successfully. able send test message properly, same message telling me outlook has problem , needs re-start. not send message causing problem in first place, , still cannot delete message. have tried setting outlook offline , re-starting (several times), can't delete message.

i tried un-installing office 365 , re-installing  it. when re-installed, outlook knew accounts, leads me think didn't re-install; had expected have set email accounts again.

i've tried command sfc /scannow windows shell. program completed , said there no corrupt files.

i still have problem, can resolve (sort of) not using gmail account in outlook. if add gmail account, tries send message, apparently unsendable reason, , outlook crashes again. solution not use gmail in outlook. , every time exit outlook, says have unsent message in outbox, message ignore.

probably, if did a complete uninstall of office 365 , re-installed, fix problem. don't know how tell outlook forget accounts. perhaps should first delete accounts in outlook , re-install office 365?

Office / Outlook / Windows 10 / Office 365 Home