Why is winlogon.exe giving me errors?
System process issues are mainly a result of conflicting applications running on your PC. Consider uninstalling any applications you are not using and using
SpeedUpMyPC to scan your system for unused process and services.
Why do I have multiple instances of winlogon.exe?
The system sometimes dedicates more resources to a specific task by generating multiple instances of one process. However this can also be a symptom of a virus or trojan infection. Make sure you always use an updated antivirus and run a full scan.
winlogon.exe is known to have 3 other instances:
Trojan.W32.Sober 
winlogon.exe is a process which is registered as a trojan.
"This Trojan ...
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Trojan.W32.Netsky & Backdoor.W32.Prorat 
winlogon.exe is a process which is registered as a trojan.
"This Trojan ...
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Trojan.W32.Rontokbro 
winlogon.exe is a process which is registered as a trojan.
"This Trojan ...
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