Vista Home Premium Backup Issue

[vegaspat]

Backup error about space on Windows disk (0x81000014)

I have Windows Vista Home Premium, and have been using the Backup tools thatcome with Vista. I've been performing backups of my C drive to an external harddrive (J).

For the most part the backup have been working, and I have tested recovering files. However today I got an error that I cannot figure out:

The last file backup did not complete successfully. Details:
"There is not enough space on your Windows disk to prepare for backing up
your files. At least 400MB of free space is required to continue.
(0x81000014)"

I have over 160 GB for free space on C. And over 134GB of free space on J.
I'm not sure where it can't find 400MB of space in all these free GBs. Any
suggestions?

I've searched the Internet and see that this is an issue quite a bit but no one ever follows through with a decent answer.

Does anyone here have an answer or solution?

Thanks.