I have created a dynamic TrueCrypt volume file, set it size to 40 GiB and put about 20 GiB of files on it. When I open the volume file properties it says "Size: 40.0 GB, Size on disk: 23.0 GB". When I try to move the volume file to another physical partition it takes a lot of time as it tries to copy all the 40 GB instead of just 20 GB that the volume file actually takes. Also, when it is less than 40 GB free on the target drive it says insufficient space even though it is more than enough space considering how much does the image file actually take. How do I overcome this? Creating a new volume file on the target drive works but needless to say I'd like a better solution.