For Plesk version 11
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1. Log into Plesk control panel.
2. Select the desired domain from "Domains" list.
3. Select "Hostings Settings" from "Websites and Domains".
4. Click on the drop down menu for "Web statistics" and select "Awstats".
5. Click "OK" button
For Plesk version 10
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1. Log into Plesk control panel.
2. Select the desired domain from "Domains" list.
3. Select "Show Advanced Operations" from "Websites & Domains" tab.
4. Select "Website Scripting and Security" option.
5. Click on the drop down menu for "Web statistics" and select "Awstats".
6. Click "OK" button.
For Plesk version 9
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1. Log into Plesk control panel.
2. Select the desired domain from "Domains" list.
3. Select "Web Hosting Settings" from "Website" tab.
4. Click on the drop down menu for "Web statistics" and select "Awstats".
5. Click "OK" button.