Reason of Google penalty and how to find it

heck the following  in your Google webmaster tools: Dashboard — Overview. If the Googlebot has problems accessing your home page, it will return a message like the following: “Googlebot cannot access your home page because it is blocked by robots.txt.” In this case, you need to remove the robots.txt in your web server root directory and submit a re-consideration request to Google. You can read more about submitting reconsideration requests here:

http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35843

Also, you should go to your home page and view the source. You should NOT see this code:

<META NAME=”ROBOTS” CONTENT=”NOINDEX, NOFOLLOW”>

This code tells Google not to index your home page, and, at the same time, not to follow the links in your navigation menu. If you see this, then remove it and submit a reconsideration request.

b. If the above test turns out negative, find out whether or not there are links pointing to your site. Googlebot can find your site just by following links. If there are no inbound links to your domain, then it will not be found, no matter how many times you submit the site to Google.

You can check this data in Google’s webmaster tools. Go to Dashboard— Links—- Pages with external links. If Google does not find any links leading to your site, consider getting links before you continue with the rest of this diagnostic testing.

2.

Does your site hide content and stuff keywords?

Check your home page first for possible hidden text and keyword stuffing issues:

1.

In your home page, press control A. This will select all, and can detect text using the same color as the background.
2.

If you cannot find a problem, try disabling the CSS using the Firefox web developer tool plug-in. Go to CSS —- disable all styles. This will show the hidden text using a CSS method. Slowly look for signs of spam in that text,  especially the kind that appears when CSS is off but is hidden when the style is turned on.
3.

If you cannot find hidden text using CSS and the Control A method, try disabling your browser’s JavaScript. In Firefox, this can be done by going to Tools— Options —Content, then unchecking JavaScript. This method can detect text that has been hidden by using JavaScript. Be cautious about what changes when JavaScript is on, and when it is off.
4.

Finally check using an SEO search engine spam detector tool. You can use this one:http://tool.motoricerca.info/spam-detector/

However, you cannot just rely on this tool. It is important to double check the source code as well. Double check every section of your site, starting with the home page, then do a sample check of your category pages, product pages, site map and other related pages. Note that stuffing keywords can relate to using a sentence that is entirely unnatural to read and appears very spammy, such as:

Buy Viagra online cialis is one of amazing SEO buy Viagraonline , take free online personality test become famous cialisViagra online buy one now.

By the way, you should also make sure that all of the sentences in your content are perfectly legible, or else the search engines will consider them to be spam.

Source : SEOCHAT.com