Firstly, you shouldn't use ANY payment services if your computer has a virus or you are suspicious that it may have as safety comes above all else.
But don't worry, there's a way through.
You can manually delete/get rid of viruses. And it's quite simple, no advanced skill required.
Here's how...
1. Run the Windows command prompt.
You can run the Windows command prompt by either clicking on the Start Menu\All programs\Accessories\Command Prompt or by pressing Windows + R on the keyboard and typing "CMD.
2. Look for the directory or folder where the virus resides. Go to the folder where the virus is hiding. Its usually resides on the Windows temporary folder or on the Windows system folder. Check partitions and drives for viruses, e.g. type "cd e:\virus"
3. Show the hidden virus and remove its attributes.
It will be easier if you can see the virus. Remove the virus attributes, which are read only, archive, system file, and hidden file. e.g. type "attrib -r -a -s -h virus.vbs"
Delete the virus. Say goodbye to the virus by deleting it, e.g. type "del virus.vbs"
(This does not cause any damage or interfere with your hard drive and rest of computer)