OK Henrick
Thanks for your reply
I use a laptop with one COM port (and in MCloader there is no more choice than COM1)
this COM1 is working with my serial programmer
It is important that you said ...

TX and RX lines (via MAX232) goes to RC6 and RC7
good bootloader file burned in the pic (16F874_20.hex from MCloader directory)
compilation (using PBP v 2.6) using good define user line (this program "blink" was tested and PIC is OK)
power on the PIC
start MCloader .. load hex file ... push program icon .... depress RESET button on PIC board

download should works beetween the laptop and te PIC ...

am I right ?