A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Hi Shaher,
When your Excel file contains a large amount of data, it will really take time to load even if conditional formatting is turned off. We can start troubleshooting the issue by opening your Excel file in safe mode. This will help us identify if the issue is caused by add-ins. To start Excel in safe mode, refer to the article below:
Open Office apps in safe mode on a Windows PC
Let us know how it goes.