Hello Atselichtchev,

Thank you for posting in our community. WebSpellChecker can be applied only to one checkbox. You can dynamically iterate thru the check boxes and to refer them to a different  WebSpellChecker.

For more information follow this link:

http://samples.infragistics.com/aspnet/ComponentOverview.aspx?cn=spell-checker

I hope this helps.

For any further questions do not hesitate to contact me.

Sincerely,

Georgi Sashev

Developer Support Engineer

Infragistics, Inc.

http://es.infragistics.com/support