i have signed in to the google webmaster & see it shows me the two site map errors ?how can i resolve them.help me for this plz
You need to regenerate the sitemap files without errors. If they are broken links then fix the site before generating the sitemap.
Try to validate your sitemap and see if it finds any errors. I use http://www.xmlcheck.com and it does give you good report if any errors are found.
You might have changed your site and the URLs listed in your Sitemap are now no more valid. Delete the Sitemap and add the correct Sitemap then the errors will not appear.