Yea this happened to me too. This is windows 8. Unfortunately there are lots of LOCK files. So I am deleting all of them. I run it again and I get the same error. Task Manager has no Bitshares client running. I know there was a bad shutdown that started this problem, then it crashed and I believe tried resetting the DB when it crashed again. Now it won't try to reset the DB.
$ find . -name LOCK -print
./chain/index/account_db/LOCK
./chain/index/account_index_db/LOCK
./chain/index/address_to_account_db/LOCK
./chain/index/address_to_trx_db/LOCK
./chain/index/ask_db/LOCK
./chain/index/asset_db/LOCK
./chain/index/asset_proposal_db/LOCK
./chain/index/auth_db/LOCK
./chain/index/balance_db/LOCK
./chain/index/bid_db/LOCK
./chain/index/block_id_to_block_record_db/LOCK
./chain/index/burn_db/LOCK
./chain/index/collateral_db/LOCK
./chain/index/delegate_vote_index_db/LOCK
./chain/index/edge_index/LOCK
./chain/index/feed_db/LOCK
./chain/index/fork_db/LOCK
./chain/index/fork_number_db/LOCK
./chain/index/future_blocks_db/LOCK
./chain/index/id_to_transaction_record_db/LOCK
./chain/index/market_history_db/LOCK
./chain/index/market_status_db/LOCK
./chain/index/market_transactions_db/LOCK
./chain/index/object_db/LOCK
./chain/index/pending_transaction_db/LOCK
./chain/index/property_db/LOCK
./chain/index/relative_ask_db/LOCK
./chain/index/relative_bid_db/LOCK
./chain/index/reverse_edge_index/LOCK
./chain/index/short_db/LOCK
./chain/index/slate_db/LOCK
./chain/index/slot_record_db/LOCK
./chain/index/symbol_index_db/LOCK
./chain/index/undo_state_db/LOCK
./chain/raw_chain/block_id_to_block_data_db/LOCK
./chain/raw_chain/block_num_to_id_db/LOCK
./exceptions/LOCK
./mail_client/archive/LOCK
./mail_client/inbox/LOCK
./mail_client/processing/LOCK
./mail_client/properties/LOCK
./peers.leveldb/LOCK