This is strange, and shouldn't happen. I think it is a matter of considering any possible causes, and eliminating the ones you know are not causing it.
What filesystem is it?
If you save files in /home/tc, are they still there next time you boot?
What other boot options are you using?
Does it still happen if you boot with the norestore boot option?
Is there anything unusual about your installation which may cause it to function differently to a normal one?