Restore Sidebar Favorites of server files/folders

My Sidebar Favorites of files and folders on a corporate server sometimes disappear after a server connection interruption. Only the favorites located on the server disappear; all local favorites are still OK. I have restored (replace) from Time Machine the "/Users/username/Library/Preferences/com.apple.finder.plist" and "/Users/username/Library/Preferences/com.apple.sidebarlists.plist" and restarted but the missing Sidebar Favorites do not come back. I'm on a MacBook Pro, El Capitan 10.11.6. I keep all my working files on the corporate server ( I don't know anything about servers). I have to believe I can get these back somehow, but don't know how other than the typical Time Machine restore. Thanks for any solution.