Have you rebooted the computer? A frozen mouse is not one of the System Check symptoms.

If it is a USB mouse, did you try a different USB port? Is this desktop? Or are you using a mouse on a laptop instead of the touchpad.?

Have you tried to do a System Restore to date closest to right before mouse freeze problem began? See if the following will work:

To start System Restore using the Command prompt, follow these steps:

1. Restart your computer, and then press and hold F8 during the initial startup to start your computer in safe mode with a Command prompt.
2. Use the arrow keys to select the Safe mode with a Command prompt option.
3. If you are prompted to select an operating system, use the arrow keys to select the appropriate operating system for your computer, and then press ENTER.
4. Log on as an administrator or with an account that has administrator credentials.
5. At the command prompt, type %systemroot%\system32\restore\rstrui.exe, and then press ENTER.
6. Follow the instructions that appear on the screen to restore your computer to a functional state.
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Once you get moving again, do the following:

Click on Start> Settings> Control Panel> System> Hardware tab> Device Manager> go down to the bottom and click on the + sign to expand the Universal Serial Bus Controllers:

Do you see any error/alert> Note what device it's for.

I can't go any further until I have some information about what you are experiencing that causes you to think you have the System Check malware

I have no information bout your system to guide you, so you will have to adapt what I tell you.
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My Guidelines: please read and follow:

• Be patient. Malware cleaning takes time and I am also working with other members while I am helping you.
• Read my instructions carefully. If you don't understand or have a problem, ask me.
• If you have questions, or if a program doesn't work, stop and tell me about it. Don't try to get around it yourself.
• Follow the order of the tasks I give you. Order is crucial in cleaning process.
• File sharing programs should be uninstalled or disabled during the cleaning process..
• Observe these:
  [o] Don't use any other cleaning programs or scans while I'm helping you.
  [o] Don't use a Registry cleaner or make any changes in the Registry.
  [o] Don't download and install new programs- except those I give you.
• Please let me know if there is any change in the system.

If I don't get a reply from you in 5 days, the thread will be closed. If your problem persist, you can send a PM to reopen it.
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