What causes missing DLL files?

Related questions

1. What is DLL in C#?
2. When DLL file is created in C#?
3. What DLL files do?
4. What is DLL hell and how does .NET solve it?
5. Why are my DLL files missing?
6. What program runs DLL files?
7. What is end to DLL hell?
8. What is DLL hell problem in C#?
9. Is DLL files com safe?
10. Can a DLL be a virus?

Tags

1. #especially
2. #malicious
3. #windows
4. #registry
5. #deletion
6. #newer
7. #hardware
8. #overwriting
9. #errors
10. #software
11. #uninstall
12. #faulty
13. #program
14. #corrupt
15. #causes
16. #infestation
17. #common
18. #malware
19. #spyware