Accu-Chek performa Owner's Booklet page 56

If your control result is not inside the acceptable range, here are some things you can do to
solve the problem:
Troubleshooting Checks
1. Check the expiry date of the test strips
and control solution.
2. Check that you wiped the tip of the
control solution bottle before and
after use.
3. Ensure that the caps on the test strip
container and the control solution
54
bottle are always closed tightly.
4. Check if the test strip was out of the
container for a long time.
5. Check that your test strips and control
solutions were stored in a cool, dry place.
Action
If either is past the expiry date, discard
it. If the control solution was opened
more than three months ago, discard it.
Wipe the tip of the bottle with a tissue.
Repeat the control test with a new test
strip and a fresh drop of control solution.
If you think either may have been
uncapped for some time, replace the test
strips or control solution.
Repeat the control test with a new test
strip.
Repeat the control test with properly
stored test strips or control solution.