JTAG stop working

[Altera_Forum]

I don't know why the JTAG stoped working ... I'm using Microtronix's Cyclone EP1C20. 

When I try to upload to the board, I got these messages :  - inside Nios SDK 5.0.1 Build: 86, uploading the kernel :  ------------------------------------------------ Microtronix Linux Extensions Version 1.4, Built June 20, 2005 ------------------------------------------------ 06/09/2005 20:44:05 - (INFO) nios2-flash-programmer: Launching Quartus Programmer to download:  D:/Programas/Altera/Nios/components/altera_nios_dev_board_cyclone_1c20/system/altera_nios_dev_board_cyclone_1c20.sof Error: Can&#39;t scan JTAG chain. Error code 87. 06/09/2005 20:44:06 - (SEVERE) nios2-flash-programmer: Unable to download SOF: D:/Programas/Altera/Nios/components/altera_nios_dev_board_cyclone_1c20/system/altera_nios_dev_board_cyclone_1c20.sof, exiting  I have tryed to auto-detect the hardware in the Quartus II Programmer, and it say to me : Unable to scan device chain. Can&#39;t scan JTAG chain.  I dont remember where these showed up too: Error: Can&#39;t access JTAG chain Error: Operation failed  I dont know what to do. I have tryed to set the jumpers back to the default, as is in Cyclone Data Sheet. Everything seems normal. I can not upload the Kitchen_sink core, because the erros of JTAG http://forum.niosforum.com/work2/style_emoticons/<#EMO_DIR#>/smile.gif , so I can&#39;t test it.  Any suggestions ??  Regards. Arthur.