I am attempting to move a file to another folder inside a TortoiseSVN repository, and the revision history is not being preserved. I have tried moving the files using the Repo-
Subversion and TortoiseSVN absolutely do preserve the file history. (It is one of the fundamental aspects of SVN.)
Two key points (which you already seem to be aware of):
You have to use the SVN move/copy/rename commands. Otherwise, SVN won't be able to know they are the same file.
When looking at the log for moved/copied/renamed, you have to make sure the "Stop on copy/rename" option is unchecked. Otherwise, the log will only go back so far.
Now, keep in mind that you need to be looking at the log for something that actually was moved/copied. Look at the log of the file that was copied. Don't look at the log of the directory you copied it from, or the directory you copied it to.