If you find that the other mentions of the phone numbers are on directory sites like DMOZ (which can take along time to get edits) you can add this code to the head section of the homepage:

Hi -

A good question to ask is do you have 400 pages that are relevant, up-to-date and useful to visitors. If you have duplicate content, empty pages and so on a decrease in indexed pages is not necessarily a bad thing. You don't want your SEO efforts diluted across multiple pages when there is only one best page and you don't want your visitors to go to a bad/old page because this would be a poor user experience for them.

My first check would be to look at your XML sitemap. If you don't have one start there (be sure to upload to Google Webmaster Tools). If you do have one check there are no issues (in Google Webmaster Tools) and also have a manual check to ensure that it is using correct tags, indexed all of your pages etc.

Also have a look at your robots.txt file - have you made any changes lately? Blocked sections from being accessed?

Content - do you have lots of pages with similar content. If so you should use rel-canonical tags so that search engines know which page should be indexed.

Find the true amount of webpages you have (and want indexed), tidy up the what and how pages get indexed and then use that number as your benchmark for amount of pages indexed.

Hope that helps,Davinia

Hi Jeff,

I had the same issue with a client last year. In a nut shell a soft 404 error is when the page looks like a regular 404 error web page but the http response header returns 200 OK. So search engines think that the page is okay (a regular webpage) but there is no content on that page etc.

Your webteam will need to identify how they are producing the soft 404 error pages (with 200OK header responses) and change that set-up in the CMS. Or, if these are old pages that are no longer required and are no longer driving traffic then archive/delete them.

Good luck,
Davinia

Hi Jeff,

I had the same issue with a client last year. In a nut shell a soft 404 error is when the page looks like a regular 404 error web page but the http response header returns 200 OK. So search engines think that the page is okay (a regular webpage) but there is no content on that page etc.

Your webteam will need to identify how they are producing the soft 404 error pages (with 200OK header responses) and change that set-up in the CMS. Or, if these are old pages that are no longer required and are no longer driving traffic then archive/delete them.

Good luck,
Davinia