How do I fix http error 401?

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Tags

1. #status
2. #means
3. #reason
4. #cannot
5. #access
6. #first
7. #password
8. #trying
9. #loaded
10. #unauthorized
11. #entered
12. #invalid
13. #valid
14. #logged
15. #until
16. #credentials
17. #received
18. #error