Hi Valery, I replaced the old version of WinEEG, and updated the driver that was included. Now WinEEG will not acknowledge the Mitsar, (Menu item "equipment parameters" is grayed out, impedance checking likewise. Switching to the old version of WinEEG again, WinEEG recognized the Mitsar. Running Windows 98 (not SE) on Compaq Armada M300 laptop (P III at 500 Mhz). Any suggestions are welcome! Thanks in advance. -- Joe