InfoPath Dev

I have a saveral infopath forms hosted in sharepoint. They were made for 2007 and later upgraded to 2010, without problems. I made changes to them a month ago without problems. Now, the changes i make, are not saved in sharepoint. I get no error while publishing. I tried deleting the xsn manually and republishing, booting the server, renaming etc., but still i get the old version i the browser. Can anyone help me?

These are published directly to a library? Not admin approved or content types? You may want to check the SharePoint log files and see if something is going awry during publishing.

It uses a content type which i Update every time i publish. Can contenttypes cause this error? There is no approval of any kind and im a site collection owner. I've done it many times before without error.