https://www.infopathdev.com:443/forums/41.aspxIf you're not sure where to ask your question, ask it here. If necessary, our moderators will make sure it gets classified in the correct board.enCommunityServer 2007 SP3 (Build: 31118.962)https://www.infopathdev.com:443/forums/thread/101710.aspxFri, 13 Mar 2015 17:35:23 GMT033a2e2d-04e2-4a9d-be01-a4634161eefd:101710Hilary Stoupa0https://www.infopathdev.com:443/forums/thread/101710.aspxhttps://www.infopathdev.com:443/forums/commentrss.aspx?SectionID=41&PostID=101710<p>I&#39;d extract the form source files (change .xsn to .cab, then copy the files out to a new folder) and open up manifest.xsf with a text editor. See if you can find anything referencing ruleSet_26 and remove that.</p>https://www.infopathdev.com:443/forums/thread/101596.aspxSun, 08 Mar 2015 21:01:22 GMT033a2e2d-04e2-4a9d-be01-a4634161eefd:101596SRAEngineer0https://www.infopathdev.com:443/forums/thread/101596.aspxhttps://www.infopathdev.com:443/forums/commentrss.aspx?SectionID=41&PostID=101596<p>&nbsp;I made some changes and saved the file. Now try to open again and I get the following error message Box and unable to open. How can I resolve this?&nbsp;</p><p>&nbsp;The form definition (.xsf) file contains elements, attributes, or structures that are not valid.</p><p>Error details:<br />The keyref &#39;ruleSet_26&#39; does not resolve to a key for the Identity Constraint &#39;{http://schemas.microsoft.com/office/infopath/2003/solutionDefinition}ruleset_name_key&#39;.</p><p>Line 1450, Position 3<br />&lt;/xsf:xDocumentClass&gt;<br />--^</p>