Trying to fax over VOIP w/ a USR 5670 PCI fax modem in Vista x64.. USR says it's compatible. Tried a couple of fax numbers several times ea - one here in town, one an 866 #. Every time it dials OK, says it's connecting (can hear the hand shaking), a few seconds of silence, then displays the message, "Remote modem Not Compatible." So it never has connected to any remote modem - not a matter of dropping connection. Should mention Vista immediately installed it's own drivers for the modem & I've not updated w/ drivers from USR. Not sure, but doubt that's the problem. Made (most) changes in Future-Nine's FAQ on faxing over VOIP. Using Line 2 on Linksys PAP2-T. The modem will dial out (using USR's Phone Tools fax prgm - for Vista x64). Thanks. The modem Diagnostic / Query thru Device Mgr all showed OK - no problems as far as Windows & the modem communicating. Two settings in Future-Nine's faxing FAQ I'm not sure about / couldn't find: #4 Disable ECM on your fax. Does this refer to a PAP2-T setting? If so, don't see it. In modem settings, under Device Mgr, there's a setting for "Data Connection Preferences > Data Protocol" for Standard or Forced EC. Not sure if this is what #4 refers to. Changing Data Protocol to "Disabled" didn't make a difference. Putting a DSL phone filter between the ATA & modem didn't matter either. Other setting in the FAQ I couldn't find is #12 "Set FXS Port Input Gain & FXS Port Output Gain to -3." Only setting for FXS I see is at bottom of the Line 2 GUI for Caller / Callee Connection Polarity. Choices are Forward or Reverse. Changing those didn't make a difference - put back to default "Forward." I assume all settings for Line 2 (for fax) should be same as Line 1, EXCEPT those mentioned in the faxing FAQ?