a question about digital clock

[Altera_Forum]

i've used a schematic file to creat a 24 counter and used a vhdl file to creat a 60 counter.they all simulated sucessfully ,and i've created symbol file for vhdl file.but when i use symbols in a schematic file to creat a digital clock,it can't compile.it shows: 

Error: Node instance "inst" instantiates undefined entity "cntm60" (60 counter) Error: Node instance "inst1" instantiates undefined entity "c24" (24 counter) and when i double click the 60 counter's symbol or 24 counter's,it shows "no vhdl file"

[Altera_Forum]

have you included the vhdl file in the project?

[Altera_Forum]

--- Quote Start ---  have you included the vhdl file in the project?  --- Quote End ---    no.now i know why i failed.thank you very much.