S.M.A.R.T. diagnostic extended test

  Hi- I am having a problem running the extended test.  I keep seeing a maximum of 10% completed & then I see a message after about 4-minutes into the test that shows status code 27.  It seems to complete the short test alright, but not the extended test.  What does the code mean & is there a way to “fix” the problem?

Thank you!