How does this work (bum CD question)?

Our IT guy came to town last week to upgrade my system from NT to Windows 2000. It didn’t work; he kept getting file copy errors during the installation and ultimately, since all the errors seemed to be clustered around files beginning with m or n, I decided it was a bad CD and got the IT guy to send me a new one. He agreed with that diagnosis.

But the thing I’m curious about is that the copy errors varied from installation attempt to attempt. One time it would be 16 files (that I was keeping a record of) and the next time it would be 15, 12 of which were the same as the first group, but with 3 new ones, and 4 of the original group were copied OK.

Can anyone explain what was happening?

Were there any processes (anti-virus, screen saver, etc.) running during the installation? Sometimes read/write operations can be screwed up by another application or scheduled process taking system resources. Try disabling any unnecessary programs or utilities and re-installing.

-Brianjedi

Thanks for the thought there, brianjedi; I could see that being a problem when installing an app. But this was a fresh install of a new OS on a newly formatted partition. I think it’s impossible to have another process running during such.

Was it the bios anti-virus boot sector change thing (actual technical term :)) kicking in?

I know my old PC had this, and even during a fresh install it would stop everything and tell me that “someone was trying to write to the boot sector” and give me an option to continue, or cancel the operation.

Interesting thought, there, Khadro. With a fresh install going on, the only processes that could be operative would have to be pre-OS boot, and that could only be from BIOS. I don’t know if my BIOS has a virus catching feature.

My original thought was how could a physically damaged CD sometimes yield up certain files OK and other times not?

Well, reading a CD isn’t a purely digital process. At the low level, it’s a messy analog problem of “how reflective is reflective?”:

I’m no tech-head, but it seems quite possible to me that a scratched CD might read differently each time you tried in. (That’s definitely true of some smudged CDs, as I know from experience.)

Here are some WAGs…

The CD might have had fingerprints on it or something else that was interfering with the read process (scratches, some kind of goo, etc).

The CD cable might have become slightly loose.

The memory or CPU might have become slightly unseated.

The CPU fan isn’t working and the processor is overheating.

What I usually do is boot from dos with a bootable floppy containing the dos CD driver, copy the CD to the hard drive, then install it from there. This is much more reliable in my experience.

Yeah, that works well, copy it to the HD first that way you actually verify it can be read.

Also, yes, sometimes the Bios is set so you can’t write to certain areas so look around in the bios & see what it has.