One-minute "Not Responding" when data is not on C: drive

I've just updated by Dell T3400 Precision to Win 7 Pro 64, and I'm getting a very annoying timeout problem.

I keep all my data files on a separate hard disk (D) so that it's easier to back them up. But Win 7 doesn't seem to like this.

Many programs go into "not responding" mode for about one minute (I've timed it) when I take almost any action: click on a button, whatever. For instance, in Firefox, when the download location is set to a folder on the D drive and I try to start downloading a file, I get the rotating blue timer icon for one minute, then the download starts. If I change the download folder to the C: drive, it works normally.

This happens on several programs, including MS Outlook 2003.

The whole computer doesn't lock up, just that app. I can still do things with the system and other open programs.

The good news is that the relatively simple workaround is to move the files to C, but the bad news is that I really would like to keep them all on D.

What I've already tried:

Clean install. I first noticed the problem with the first Win 7 install on this machine after I started up Outlook 2003. I eventually found that it worked fine if Outlook.pst was on the C: drive. I did a clean reinstall of Win 7 and loaded Office first and tried Outlook again. Same result. I later noticed that other Office programs exhibited the same behavior.

Power Settings. I found some people online complaining of a similar problem on their laptops if the power settings were set to anything other than High Performance. I've set it there. Not change.

Hard disks. I read some people suggesting that problems like this could be a sign of a hard disk failing or bad HD connections. It's not the first because it happens on both of my two internal data drives, and not the second: I opened the box and reset all HD connectors. Also, this wouldn't explain why the timeout is almost always exactly one minute.

Multiple active partitions. It turns out I had accidentally set one of the data drives and my external HD as active partitions, in addition to C:, which has the OS. I made them inactive. No change.

Does anyone have any ideas about what's happening here and how I can fix it?

Thanks.

No! I hadn't thought of that. Would it result in such a consistent delay?

I just set most of D: to be indexed, but there are lots of files. How long should I expect it to take, and how can I track the progress?

I'll give it an hour or two and check again. Thanks for the suggestion.

Will do (especially if it doesn't work!).

In the meantime, if anyone else has any ideas, please chime in.

I don't think it worked. But I'll let it run overnight and check in the morning.

No, that didn't do it, unfortunately.

Someone at another forum suggested I check any programs that use the Explorer Shell. The only one was NVIDIA's control panel. I tried uninstalling that, but no joy.

Any other ideas?

I think I've solved the problem. There's an old internal modem that I used for dialing numbers from my address book and for the rare fax I had to send or receive. I hadn't noticed at first that Win 7 didn't recognize the device, and after trying and failing to locate appropriate drivers for it, I simply disabled it. That seems to have fixed the problem, knock wood.

I've ordered a new modem that is supported by Win 7, for all of $15, including shipping, and should have it in a couple of days.

Thanks for your help.