Since I don't have WMWareTools installation.iso and don't know how to configure ftp,I share files between WinXP(host OS) and Linux(WMWare OS) by using command:
mount //192.168.0.100/me /mnt/Win
in which, "192.168.0.100" is the IP address in Windows in the local network, "me" is the folder under windows I want to share, /mnt/Win is the mount point. and ping command gives positive reply in either Linux or Windows.

This solution had worked well for a period of time,
but failed just now, prompted these on screen:
session request to 192.168.0.100 failed(Called name not present)
session request to 192 failed(Called name not present)
I am sure there are no spelling errors.

anybody who can help?

Did you try a ping to 192.168.0.100 ? Does it still respond?

Yes,I did try a ping to 192.168.0.100 ,as I said it gave positive reply.

What type of file sharing are you using? Samba? of NFS? could you post the config files for what ever file sharing you are using.