Published Nov 2, 2009

I’ve been using a Time Capsule to back up my Mac for some time now, and have been very satisfied. I was wishing that I could run some kind of over-the-air backup for my wife’s laptop, which runs Windows XP, too. So I attached a USB hard drive to the Time Capsule, and tried to mount that on the Windows XP laptop. First I did it the wrong way, and there was much sadness. Then I did it the right way, and life was easy. I couldn’t find a description of how to do it right in a quick Google search, so here’s my story. It’s probably true for an Airport Extreme Base Station too, since that and the Time Capsule are similar.

The Wrong Way

Apple advertises that you can share disks attached to its wireless routers using the AirPort Disk Utility, if the clients are either Windows machines or older Macs. So I downloaded the AirPort Disk Utility, ran it, and easily mounted the disks.

Then I restarted, and the drive letters assigned to the disks changed. Obviously, that would be a problem if I tried to run backup software, which would try to copy files to a given drive that might or might not be there.

The Right Way

So away went the AirPort Disk Utility, and instead I:

  1. Went to the Start Menu, and opened My Computer
  2. From the Tools menu, selected Map Network Drive
  3. Picked the Drive Letter I wanted
  4. For the Folder, typed in \[IP Address of Time Capsule]\[Drivename] — so, if your Time Capsule was at, and your backup drive was named George, you’d type \\George
  5. Hit Finish. And there was the drive!

So, if you want to consistently connect your computer running Windows XP to a USB drive attached to a Time Capsule (and probably and Airport Extreme Base Station), you need to do it through Windows XP, and not through the AirPort Disk Utility. Simple!


I’m unclear on why you would need an external USB drive. Are you backing up so much stuff to the Capsule that you can’t handle multiple machines on it?

In any case, there’s step-by-step instructions available here on how to use Bonjour to backup a Windows machine to the Capsule’s internal drive…

Oh, also — did Windows switch from using double-backslash to double-forwardslash for referencing network locations? I haven’t really been using Windows much for a while, but definitely the last time I was using XP, the beginning of network drives was “whack whack”. (The folks I worked with at MS referred to the backslash as “whack”. There are a lot of backslashes in MS-land, so you really need a shorter name for it…)

You are totally correct about the slashes vs. backslashes; I fixed it in the entry so as not to screw up anyone who comes here via google.

There were two reasons I wanted to use a drive hanging off the Time Capsule:

  1. I bought the small Time Capsule, and I was greedy to keep that little space for my own nicely-versioned Time Machine backup
  2. I had an extra drive lying around and was looking for a good use for all that space

I’ll allow that both are kind of silly.

When I tried essentially what they described, as in my “Wrong Way” section, I ended up with a drive that changed assigned letters between boots — a problem if I wanted to use backup software that referred to drive letter, rather than UNC path. So I tried the other way, and got a static drive letter between reboots.

(Maybe the real problem was that I needed smarter backup software.)

Anyway, the point is: my google-fu didn’t turn up the result you suggested, so hopefully this entry is written such that, should I ever need to figure all this out again, google will serve me up this page as the result.

Hmm. I need to set up Xta’s drive to backup to my Time Capsule some time in the next week or so — I’ll try to remember to let you know whether the Windows Airport utility works right on her machine (Vista) to get a stable drive letter, and any magic tweaks I discover in the process…

So, mapping to a drive letter with Map Network Drive seems to work for her, but so far she hasn’t been able to persuade the Windows backup utility to actually backup to the drive. Haven’t tried using Airport Utility yet.