Avast is blocking my website - how can I stop blocking?

Avast Free Antivirus / Premium Security
1

Hi.
Avast started to block my website www.rychladieta.cz. There are no any viruses, worms or any other problems.

That is problem for my business.
How can I stop this blocking ASAP?

Michal

2

→ http://sitecheck.sucuri.net/results/www.rychladieta.cz/
→ http://zulu.zscaler.com/submission/show/ea8f445df4117a404cb9edc6fcf7e915-1411378003

3

We started to block this website due to massive spam e-mail campaign.