If you are having too big Excel file then try the following measures:
• You can reduce the size of pictures.
• Reduce formatting from unused cells or rows.
• You can zip or split the Excel workbook.
• Reduce the size of Pivot table.
• Even you can use XLSB file format
• Use Professor Excel tool to reduce the file size.
• If there is some content that is unused, remove it.
If still you are facing any issue with your Microsoft Excel then please make a call at Microsoft Customer Care Number UK for resolution.