I am new to BTC mining, even totally new to bitcoins. I closed and restarted my GUIMiner and all my bitcoin shares were gone. What am I doing wrong? Is there a way to persist these shares across GUIMiner restarts?
Your shares are towards a block, once a block is completed you start on a new block and go back to 0 shares. Depending on your pool, you get paid per block or per share. Don't worry, if you look on your pools website you should be able to find what you made off of the block and how many shares you contributed.
Restarting GUIMiner will not remove your shares, your shares are automatically recorded through your pool.