VL 5.1 is three years old now. Not many folks are running it at this point. The software repository is gone and it is effectively completely unsupported at this point. It may be awfully hard for you to get an answer. Even worse, VL 5.1 has lots of unpatched security vulnerabilities and new security updates are NOT being provided anymore.
I honestly think it's time for an upgrade. If you're a KDE sort of person then go with VL SOHO 5.9.1.
eMachines EL-1300G desktop, 1.6GHz AMD Athlon 2650e CPU, 4GB RAM, nVidia GeForce 6150 SE video
CentOS 6.5 (will try VL64-7.1 soon)
Toshiba Satellite A135-S4727, Intel Pentium T2080 / 1.73 GHz, 2GB RAM, Intel GMA 950
HP Mini 110 netbook, 1.6GHz Intel Atom CPU, 2GB RAM, Intel 950 video, VL 7.1