Hopper virus infects .VBS files and Word documents, as well as HTML files. VBS/Hopper.A infects other .VBS files by prepending it's code to the original file.
Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.
A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:
Check for the latest database updates
First check if your F-Secure security program is using the latest updates, then try scanning the file again.
Submit a sample
After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.
Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.
Exclude a file from further scanning
If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.
Note: You need administrative rights to change the settings.
Some variants of this virus family also infect HTA and HTT files. Some of them lower the security settings of IE's zones. To ensure that the virus works on all platforms, when infecting VBS and DOC files, it comments out the HTML-specific part of itself. It infects documents when closes them.
Some variants of VBS/Hopper are able to infect Excel files as well.