I have replaced windows 8 with ubuntu 12.10 , and after installing i can't open hdd and i get this Message unable to mount location
I have very important files on my hhd therefore I can't formate it. What should I do to get to my harddrive?
From your comments I think that you have formatted your drive before/during installing Ubuntu. The fact that reinstalling windows also asks for a format confirms this: windows cannot use the Ubuntu file-system.
This means that you should STOP adding stuff to your harddisk. No installs, nothing. If you want any chance of data-recovery, you need to start doing everything from a live-CD or a USB.
Data-recovery is hard. You formatted everything. It is next to impossible to help you with this online if you have limited knowledge yourself, but I can explain the path you can hope for.
try to run a live disk to access your data and get backup of it
c:
)? But what happens now? you are booting your computer, you see ubuntu, and then? You must be doing something to get that error. Does de boot-process show this error, do you do anything in Ubuntu to get this error? Please describe what is going on exactly. step by step. What did you do, what do you do, when do you see what. It takes some effort, but it's the only way the situation will be clear. Please don't only comment, but edit the important information in your question.