If you upgraded to 12.5 and are stil unable to open a rolled over return by simply clicking on it try this.
go to c:program filescch small firm servicesatx2012
scroll down and double click on " sfs.max.rolloverservice" (application) or right click then hit "open"
then immediately double click the return you are trying to open. it has worked for two returns for me so far. hope it helps.