This SP 2019 farm is connected with OOS and I can view online Excel files stored in SharePoint, but I get the Health Error:
[MissingWebPart] WebPart class [e6002ce8-69ee-168a-8f7c-a1d98d51da29] (class [Microsoft.Office.Excel.WebUI.ExcelWebRenderer] from assembly [Microsoft.Office.Excel.WebUI, Version=18.104.22.168, Culture=neutral, PublicKeyToken=71e9bce111e9429c]) is referenced 1 times in the database [ContentDB], but is not installed on the current farm. Please install any feature/solution which contains this web part.
Web.config file was already modified on all servers in the farm to add the entry into the web.config file since this farm was set up like this link specifies
I also checked C:\Windows\Microsoft.NET\assembly\GAC_MSIL\Microsoft.Office.Excel.WebUI\v4.0_22.214.171.124__71e9bce111e9429c and the dll is there.
Any idea about how to clear out this Error from Central Administration>Review Problems and Solutions?