Check in time ORD

Hey,

so I'm flying tomorrow ORD-FRA-XX, and ORD-FRA is on United, and FRA-XXX is on Lufthansa. I had bought this ticket through lufthansa.

I cannot do online check in for some reason, I have spent a good hour with both United and Lufthansa.

I will reach airport at 4.40PM for a 6.05PM flight,(this is the earliest my bus gets to the airport), I will not be checking in luggage, just a carry on.

Will I be allowed to complete check in at about 4.45PM for a 6.05PM flight at the airport?

thanks,