If the HDD is missing you must replace it since I've yet to find a machine that does well without it.
"disc" may mean the CD or DVD media. Since these are not free you can either beg for a copy from your company/coworkers or consider committing a small crime?
Bob
Hello!
I had this computer at work and what to re install the software but the disk that came with computer are missing.
How i can do this with out buying a new disk? Help

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