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I'm trying to install Windows 7 using Boot Camp Assistant. Now the boot camp is on task "Formatting the selected drive" and it has been going on three hours and it is not even on the half way. How long this task should take normally, or is this normal? Or is task frozen somehow?

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up vote 3 down vote accepted

The formatting should only last seconds. The behavior which you're experiencing is not normal at all.

I would cancel the installation and verify the disk.

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Thanks, it took long (4 hours) but everything worked out fine after all. – jrara Dec 29 '11 at 10:32
You are very patient :). I'd still like to know why this has taken so long? I've never experienced this. – gentmatt Dec 29 '11 at 10:35
I really don't know, there is nothing special in my setup. Macbook Pro is a bit old (late 2008) with 10.7.1, so maybe that is the reason? – jrara Dec 29 '11 at 19:31
I don't think so. I did an install with 10.7.1 and Windows 7 on a Macbook Pro late 2007. – gentmatt Dec 29 '11 at 19:51
Perhaps it did a "secure erase"? This would cause it to overwrite the whole drive (once, or multiple times) with zeros. That can take a very long time on larger drives. – oKtosiTe Jul 2 '12 at 13:34

It will take a while if it needs to download the Windows support files prior to burning the disk. The actual speed depends on your network bandwidth and traffic.

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You're supposed to set up a partition and format it as exFat. Then download the windows drivers into that partition. Next, go into windows and install the drivers from that exFat partition.

If you select a Mac partition to download into, it spends hours chasing its tail until it realizes there is nothing for it to partition. Silly software!!!

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The formatting should last undefined amount of time, as there are many factors potentially involved, such as disk encryption or using slow external USB drives.

Before cancelling the task, you should verify if there is no progress indicated by the app, for example by marking the position of progress bar with some other window or mouse cursor, and checking the progress after 1h.

Currently accepted answer is wrong, as evidenced by "Thanks, it took long (4 hours) but everything worked out fine after all. " and my own experience of the issue.

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