I have a SBS server, SBS SP1, Win 2k3 SP2 with a fax problem. Faxes are frequently partially received and it takes several tries to send a fax. The normal fax machine works fine on the same phone line. I keep getting messages like:
"Reception error" "Unknown fatal error" "0x0000000c" 5/2/2008 14:49:06 5/2/2008 14:49:52 "U.S. Robotics 56K FAX EXT PnP" "C:\Documents and Settings\All Users\Application Data\Microsoft\Windows NT\MSFax\Queue\1C8AC8532A8F2.tif" 0 "609-448-xxxx" " " "" " " 0
in the activity logs. I updated the modem firmware and switched to the USR provided driver. This did not help. I disabled compression and reduced the port speed to 9600 baud which also did not help. The modem is a USR5686E.