Disk Director won't create new partition

I'm trying to create a new partition out of the existing partition (C: drive). everything seems ok until I commit. It shows the pending actions and gives me a message that I must reboot.

I allow it to reboot and Acronis does some partition checking and synchronizing with the OS but no partition is created and the C: drive doesn't get any smaller.

Once (I've tried several times) I got an invalid partition size message but other that that nothing.

 

I have exactly the same problem. I want to create a new partition in my C drive. There is 72GB of space, so there is plenty of room. I go through the procedure, click commit, immediately I get a message saying I have to re-boot to complete the operation. I re-boot, there is a message that Acronis is synchronising the drive, assigning a new drive letter.

Once the machine has re-booted there is no new partition. The C drive is exactly as it was before. I tried creating a partition on another drive, exactly the same thing happened. Acronis just will not create a new partition, but there's no error message, nothing at all to indicate what the problem is. Any ideas?

Windows XP Professional, SP2, all security updates installed.

ADDED I think the problem is caused by Windows, or some recent change to Windows security setting, denying Acronis access to the drive, therefore preventing it from changing the drive structure. I have three drives, Acronis cannot do anything with the first two, where I have my operating system and page file installed. But on the third drive, which has NO Windows system files I CAN resize, partition, do whatever I like.