An unknown problem is just that. It is a problem that is unforeseen or that a person is not aware of. When there new programs being release there are sometimes problems that are unknown.
it depends on the context initial (as your initials) - Initial initial (as in first) - erste/erster/erstes
what is initial correspondence
My first initial is A.
Initial
initial speed means first
The initial concentration of A was 0.05 M.
The plural form of initial is initials.
No. He/She cannot initial
The answer to what is Georgia's initial is GA, because Georgia is the state and Atlanta is the capital.
initial - final / initial x 100
Follow that initial(!)- with a period.
The Initial Command was created in 1987.