Windows 7: How do I turn on indexing for a SUBST'd drive?

I've got a SUBST for a folder to drive letter P:

I have noticed that exploring these folders from P: is now INCREDIBLY slow, taking up to a minute sometimes to show files. I'm showing them as general files and not thumbnails, so it's not that.

Looking at the original folder in explorer is lightning fast.

I've checked the indexing options and indeed the folder where my files are stored is checked as indexed. I can see my P: drive in the list, but clicking on the checkbox won't do anything.

Does anyone have any clues as to how I can fix this?

(Running Windows 7 just to be clear).

HI,
welcome to sevenforums. There are many knowledgeable peeps around here. (I don't include myself). But here's my fix effort.

Things to try.
SYSTEM must have full permissions on the folder in question.
Add the path to the indexed locations.
Try rebuilding the index.

One of these may do the trick.

Thankc cyclic,

The system has all permissions set, and the permissions aren't any different to any folder on the PC.

"Add path to indexed locations" - what do you mean by that? The indexing options seems to see P: , but won't let me check it in the list.

Yep, tried rebuilding, but no change.

Go to control panel and find indexing options. The front panel shows the currently indexed locations.
Click the advanced button and the screen will change to allow you select a new location to add to those current. It will only work after a restart.