I don't think I can help, at least not without a lot more information.

From your two posts ( and your blank profile ) here is what I can put together:

You are not a native english speaking person, or are trying to hide the fact that you are.

You have two computers, one desktop, one laptop

You know little about computers

You know nothing about Linux

On your laptop, running Fedora 7, you received a manipulation error

You attempted to reinstall Fedora 7, you received errors indicating it could not find root.


Some information that may help:

Where did you get that laptop from?
Is it a dual-boot machine?
If so, what other OS is on it?
Who installed Fedora on it?
Does anyone else have access to it?
How long was it working before you got this error?
What were you doing when you received the manipulation error ?
What type of hard drive is it?
How is the hard drive partitioned?
Are there any encrypted partitions on it?
What does the /etc/fstab file look like?

Several programs could have caused the first error.
If you received it when attempting to log in, possibly someone trying to edit the password file with vi?