Errors When trying to upgrade from 7.04 to 7.10

Hello all So Im pretty new to linux, I understand the basic commands and I have to upgrade my servers to 8.04. I have 1 and 7.04 and 1 and 7.10. Im trying to upgrade the one at 7.04 and I was able to download and update all of the old updates from the old repositories. I was then able to install the update-manager-core. However when I try to run the command do-release-upgrade i get the following errors. # do-release-upgrade Checking for a new ubuntu release Failed Upgrade tool signature Failed Upgrade tool Done downloading extracting '/tmp/tmpQPspbm/gutsy.tar.gz' Traceback (most recent call last): File "/usr/bin/do-release-upgrade", line 45, in <module> fetcher.run() File "/usr/lib/python2.5/site-packages/UpdateManager/Core/DistUpgradeFetcherCore.py", line 160, in run if not self.extractDistUpgrader(): File "/usr/lib/python2.5/site-packages/UpdateManager/Core/DistUpgradeFetcherCore.py", line 98, in extractDistUpgrader tar = tarfile.open(self.tmpdir+"/"+os.path.basename(self.uri),"r") File "/usr/lib/python2.5/tarfile.py", line 1139, in open return func(name, "r", fileobj) File "/usr/lib/python2.5/tarfile.py", line 1200, in gzopen fileobj = file(name, mode + "b") IOError: [Errno 2] No such file or directory: '/tmp/tmpQPspbm/gutsy.tar.gz' Can anyone help please?

hi i am moon shahzad i installed linux redhat server edition in graphical mode i want to convert it text mode how can i convert it text mode pls tell me.