Can no longer mine please help seems block chain is wrong and broke.

SO after downloading and mining for a number of hours all am seeing is in red the following errors. Please can someone help and spread some light to this problem.

2807584ms th_a fork_database.cpp:41 push_block ] Pushing block to fork database that failed to link: 0030dedf9d036bf46c561cef34529059661d834f, 32
02783
2807584ms th_a fork_database.cpp:42 push_block ] Head: 3202773, 0030ded5dd067fe75498b5badc9ca1b16dfcfe38
2807584ms th_a application.cpp:442 handle_block ] Error when pushing block:
3080000 unlinkable_block_exception: unlinkable block
block does not link to known chain
{}
th_a fork_database.cpp:62 steemit::chain::fork_database::_push_block

{"new_block":{"previous":"0030dede2634ed7469acf226cb5f3a5358a493eb","timestamp":"2016-07-14T23:06:06","witness":"steemit3","transaction_merkle_root":"0000000000000000

000000000000000000000000","extensions":[],"witness_signature":"1f016e65e27c3fac50ce45556c94752d479811c2d50c54ee0b455e0afd8eb4036d25d060ae2fbcc2310ffc557563b31507b53264803
e16f45d632c3f61d64b0036","transactions":[]}}
th_a database.cpp:537 steemit::chain::database::push_block::<lambda_824f109362864823e8529d65b634e20b>::()::<lambda_f997e4c962d5637a487c475147bf64f9>::operator ()
2807600ms th_a fork_database.cpp:41 push_block ] Pushing block to fork database that failed to link: 0030dee01606fb126a174f694fa92cd821405d43, 32
02784
2807600ms th_a fork_database.cpp:42 push_block ] Head: 3202773, 0030ded5dd067fe75498b5badc9ca1b16dfcfe38
2807600ms th_a application.cpp:442 handle_block ] Error when pushing block:
3080000 unlinkable_block_exception: unlinkable block
block does not link to known chain
{}
th_a fork_database.cpp:62 steemit::chain::fork_database::_push_block

{"new_block":{"previous":"0030dedf9d036bf46c561cef34529059661d834f","timestamp":"2016-07-14T23:06:09","witness":"steemit15","transaction_merkle_root":"000000000000000

0000000000000000000000000","extensions":[],"witness_signature":"200f895b6c2d08dd9f4ca36cd6d205326d9d3e67e9ca7b17cd10da7ef6b6d7812b13c90ed8d045e5161ddb7ad0a82dfd81e0e9f895
0de98cf306356377a0ce1b97","transactions":[]}}
th_a database.cpp:537 steemit::chain::database::push_block::<lambda_824f109362864823e8529d65b634e20b>::()::<lambda_f997e4c962d5637a487c475147bf64f9>::operator ()

is all I keep on getting red errors and no mining. Tried to delete all block chain start freash but keeps coming back.