Malware problems

[googinup]

Hi... every one what could be the reason for malware problems for a site??How does it effect for a site??

[kokopelli]

Malware on a site could be the result of many things, or a combination thereof:

1. Bad security by your webhost that allowed malware to be uploaded;
2. A badly formatted/executed script that allowed the same;
3. Site credentials being compromised due to a weak password, etc.;
4. Malware/virus on your computer, that was uploaded to your site;
5. Using a free theme that includes malicious code;

... etc.