When I export results to Excel or CSV format, strange characters appear. For example, quotes are changed to €œ (open quote) and € (end quote). The character  appears in various places. There are others. This has been going on through multiple versions of limesurvey and Excel. I currently have Excel 2013. Is there anyway to remedy this?

That looks like a issue with UTF8 Encoding in the workflow. That can be an issue in the database, in the application or in the browser.

This is not directly related to LimeSurvey and can happen everywhere.
E.g. digwp.com/2011/07/clean-up-weird-characters-in-database/

But first try to change some settings during the import into Excel (or use e.g. LibreOffice to import into a excel file)
www.howtogeek.com/howto/microsoft-office...ext-into-excel-2007/