Clearly stated driver installation commands do not work from command line in terminal
 

I have downloaded modem and printer driver installers to get the hardware working with my Linux. In both cases, I am given commands to type to install the drivers. I go to the Red Hat Main Menu, then to System Tools, then to Terminal, and I bring up the Terminal window. I have my user account command prompt and I type these commands exactly the way they are stated in the intsall guides that are part of the driver downloads. They do not work. They produce messages--"command not found" or "no such file or directory." When I type " su " and then my password to get my root account prompt, I type in the same commands and get the same messages. I'm basically very new to Linux and not good with commands yet. How do I get these commands to work so I can install the drivers?

To install a driver, you must be root. Are you using "su" or "su -"? Using the dash should setup your environment with the proper paths. What commands are not found, and which files are missing? A little more info about where the process is falling apart would be helpful.

First, I tried to install a PCTEL LINUX Modem driver that I downloaded. I typed-- "tar zxvf pctel-0.9.6.tar.gz" with and without the quotes and I got the message--command not found. When I tried to enter the cd directory by typing "cd pctel-0.9.6" it told me--no such file or directory. I did not go into root with su - (dash), just with su . I tried a Lexmark printer driver with the same type of command and got the same results.

You need to install the tar command. It is an often used command and should be in the /bin directory.

I have a hard time believing you've got any kind of a normal redhat install and yet somehow managed to drill down into the install options and then decided to *not* install tar for some reason, most likely you chose a sane default installation, is this true? If so, how about doing "which tar" at the command line, it should show the full path to the command.

I recommend you log out from the menu and log back in as root before doing administrative things like installing drivers, it should put all the necessary commands in your path so you don't have to su or type full path names. When finished log out and back in as your normal user name.