I keep receiving this error message when attempting to sign in. How can I fix this? 

cId: B7F3DA624C9349C680EAE1324C97541A
app: Mail
st: 500
reqid: undefined
wsver: undefined
efe: undefined
ebe: undefined
et: ClientError
esrc: Bootstrap
err: TypeError: undefined is not an object (evaluating 'Owa.mail.bootstrapMailModule')
estack: runBootstrap@https://outlook.live.com/mail/?bO=2:209:40
global code@https://outlook.live.com/mail/?bO=2:223:21
ts: 7/10/2018 12:43:15 PM