One of my XP systems developed a strange problem: while trying to start a disk defragment, I get:

MMC cannot open dfrg.msc. This may be because the file does not exist, is not an MMC console, or was created by a later version of MMC.

I look around the net, and find all sorts of answers (of which, none work).

Then I carefully analysed the error string:

file does not exist: false… the file is there

is not an MMC console… possible, as I had to do a repair install of windows XP recently

later version of MMC… possible, but should have been picked up when I did my MS updates.

I then start to thinking: I use autopatcher to quickly apply any new patches (particularly after a repair install, as re-downloading updates can take a very long time).

Its possible that autopatcher installs a new version of MMC, and I forgot to reinstall it after the repair install… sure enough, autopatcher has MMC3.0 marked as not installed…

I install it, and disk defragmenter is now running again. 🙂

Although autopatcher is great for the type of work I do (I often reinstall windows… for various reasons), I guess I need to be aware of its limitations.