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1) try making sure that you have rights to write into that partition. Here is an example mounting a FAT32 partition with permissions for any user to both write and read:
/dev/hda1 /mnt/win_c vfat uid=500,gid=500,umask=000,exec,dev,suid,rw 1 0
This line has to be added at /etc/fstab (as root) and it assumes that your first partition is FAT, and it's mounted at /mnt/win_c. Simply change the harddrive partition you want to mount (hda2, had4, whatever) and see if it helps. Remember to create a directory to mount your partition as well (I created a directory at /mnt called win_c as you can see
). Hope this helps.
2) never connected to Internet with Linux and modem, sorry.
3) Try removing your sound card, then run (as root) sndconfig and see if it helps. If it return an error, you might need to install sndconfig. It's shipped with your Redhat CD's.