unable to delete specific items from history
I am running the current versions of Safari and OS X Yosemite on my late 2012 Mac Mini. I like to keep 6 months of history so deleting all of my history is not something I wan to do. The history items that I cannot delete are state government sites that I visited over 6 months ago and all url's end with .aspx. An ASPX file is an Active Server Page Extended File, developed by Microsoft. I have tried restarting Safari and my computer and deleting these history items again. I have gone into Preferences/Privacy and attempted to remove any data related to these sites. I delete the history and it instantly reappears. Any help with removing these files from my Safari history would be appreciated.
Mac mini, OS X Yosemite (10.10), iPod Classic, iPad Mini, iPhone 5S