How to Remove “YDefUser.dll”

What is YDefUser.dll?

The file named YDefUser.dll is developed by Yahoo! Incorporation. The file is digitally verified and has a signature provided by Verisign incorporation. The company certifies the file to be safe and reliable. It is used by the Yahoo messenger and other services developed by the company. The threat level is 1.

YDefUser.dll is located in C:\windows\temp\~\ydefuser.dll. The size of the DLL is 53.5 kilobytes. The version of the DLL known is The file being a non-system process has no consequences if removed due to a virus or malware infection. It won’t have any impact on the performance of the Windows operating system if disabled or removed.

Affected Platform: Windows 2000, XP, Vista

How to check if your computer is infected with YDefUser.dll malware?

Keep an eye for the following symptoms to check if your PC is infected with YDefUser.dll malware:

  • Unstable internet connection
  • Browser redirects to unwanted websites
  • PC performance slows down
  • Browser is bombarded with hordes of popup ads
  • System screen freezes repeatedly

If you find any of the above mentioned symptoms, take the following steps to be sure about the malware infection:

1) Press CTRL+ALT+DEL keys to open Task Manager.

2) Go to the process tab and right-click on the YDefUser.dll file and open its location.

If the file is located outside C:\windows\temp\~\ydefuser.dll, then you should take measures to get rid of the malware.

How to remove YDefUser.dll malware from system with Comodo Cleaning Essentials?

Comodo Cleaning Essentials (CCE) incorporates antivirus software with unique features like auto-sandboxing to identify and obstruct every suspicious process running on an endpoint with a single click. To remove YDefUser.dll malware using CCE, follow the steps mentioned below:

Step 1: Download the CCE suite.

Step 2: To start the application, double-click on the CCE.exe file.

Step 3: It then probes the antivirus to initiate a full system scan to identify and remove any existing malicious files.

Step 4: If threats are found during the scanning, you will be prompted with an alert screen.

Step 5: Comodo Cleaning Essentials will remove YDefUser.dll malware from your computer including all other malwares!

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