Inspyder InSite
Check your entire site for spelling mistakes and broken links in seconds! InSite is different from a standard IDE spell checker because it checks pages that the user sees, not pages under development. If your website is database driven, or pulls content from another source, your IDE spell... InSite integrates with the Windows scheduler to check such sites on a regular basis. ... The results show where the spelling mistakes are found, and which pages contain broken links or missing content (such as images or style-sheets).
http://download.inspyder.com/InSiteTrialSetup.msi - 5Mb - Download - Screenshot

ASP Spell Check
ASP SpellCheck is an international spell checking component for Microsoft ASP (VBScript) web applications. ASPSpellCheck provides international spellchecking for your ASP applications. It is suitable for use with W3C HTML and XHTML applications, and has a good degree of accessibility. ... Uses Include: Spell check any form in your website, intranet or web-application. ... You can also spell-check entire Iframes. ... Adding a spell-check to an existing webpage can be performed in minutes. ... Build spell check into your WebMail application with ease.
http://www.aspspellcheck.com/downloads/ASPSpellCheck_trial.zip - 2Mb - Download - Screenshot

CSE HTML Validator Professional
CSE HTML Validator Professional is a fast, powerful, highly user configurable, and easy to use professional web development tool that helps you create syntactically correct and accessible HTML, XHTML, and CSS documents. The new HTML Tidy Tool can even fix HTML and XHTML (and more). ... CSE HTML Validator is designed for both HTML beginners and professionals who want to make sure that their website visitors do not leave their site because they run into problems caused by poorly written HTML. ... The latest version of CSE HTML Validator includes accessibility checking (Section 508 and WCAG),...
ftp://ftp.htmlvalidator.com/pub/htmlval/csesetup.exe - 4Mb - Download - Screenshot