Your group is currently "mkpasswd". This indicates that your gid is not in /etc/group and your uid is not in /etc/passwd. The /etc/passwd (and possibly /etc/group) files should be rebuilt. See the man pages for mkpasswd and mkgroup then, for example, run mkpasswd -l [-d] > /etc/passwd mkgroup -l [-d] > /etc/group Note that the -d switch is necessary for domain users. student@winxp04 ~ $ cat.exe /cygdrive/c/lab4/wiadomosc1.txt | socat.exe - UDP:194.29.169.27:5060 SIP/2.0 200 Ztit-custom-header: 5dac06541a5a4e87dd6ff8e0ce0fd374 Subscribe wysli j do: njizyh3GAtoCg Via: SIP/2.0/UDP 194.29.169.52:5060;rport=1178;branch=z45fdd To: "Turek" ;tag=c97b4d1cb1f3d0da549e06a8d482ef63.7ba2 From: "Turek" ;tag=bhhgffff Call-ID: 175422.888770000 CSeq: 835 REGISTER Server: OpenSIPS (1.6.2-notls (i386/linux)) Content-Length: 0 student@winxp04 ~ $ cat.exe /cygdrive/c/lab4/wiadomosc2.txt | socat.exe - UDP:194.29.169.27:5060 SIP/2.0 200 Ztit-another-header: daaadf9ce77af565d03753a2d201851a Via: SIP/2.0/UDP 194.29.169.52:5060;rport=1179;branch=znbgggchhdf To: "tine" ;tag=c97b4d1cb1f3d0da549e06a8d482ef63.ce2 9 From: "Turek" ;tag=msdsdsdfvmo Call-ID: 44322315.12454554 CSeq: 496 SUBSCRIBE Server: OpenSIPS (1.6.2-notls (i386/linux)) Content-Length: 0 student@winxp04 ~ $ cat.exe /cygdrive/c/lab4/wiadomosc3.txt | socat.exe - UDP:194.29.169.27:5060 SIP/2.0 200 Media Server URI: 1010@sip-tine Ztit-proxy: 194.29.169.16:5080 Via: SIP/2.0/UDP 194.29.169.52:5060;rport=1180;branch=fffggsddfas To: "tine" ;tag=c97b4d1cb1f3d0da549e06a8d482ef63.1eb 8 From: "Turek" ;tag=fdghhdf Call-ID: 4434535315.125434 CSeq: 574 PUBLISH Server: OpenSIPS (1.6.2-notls (i386/linux)) Content-Length: 0 student@winxp04 ~ $