Excel charts: I just installed High Sierra and can no longer use Excel charts. What happened?

Did you consider contacting Microsoft?

More information would be required for someone on this site to help, much more, such as the Excel version you're using: Writing an effective Apple Support Communities question.

You did not bother to mention which version of excel you are using. Older versions may not be compatible with HS.

FWIW, charts work fine in Excel 2016 in High Sierra.