I would rearange code as follows and try.

select mytable
for i=1 to 10
	DO CASE
	CASE NOT seek(i,'mytable','id')
		messagebox('ID '+allt(str(i))+' Not Found!',0+16)
	CASE mytable.status='C'
		messagebox('The operation will ignore from tube ID '+allt(str(i)))
	OTHERWISE
		insert into mycursor value(i)
	ENDCASE
endfor

>I have the following code:
>

>select mytable
>for i=1 to 10
>if seek (i,'mytable','id')=.f.
>messagebox('ID '+allt(str(i))+' Not Found!',0+16)
>return
>endif
>if mytable.status='C'
>messagebox('The operation will ignore from tube ID '+allt(str(i)))
>loop
>endif
>insert into mycursor value(i)
>

>The problem is that the code ignore from my 'Loop' (the id inserted even mytable.status='C')
>Who can help me?