Problem opening Excel docs

Problem opening Excel docs

Hello,
I have some issue opening an Excel document. I uploaded an Excel spreadsheet with extantion xlsx which is 3.5mb. While uploading i unchecked the option to convert to zoho docs format because i want to preserve my format of Excel spreadsheet. After the document was uploaded, i'm trying to open it but i'm getting a message saying "Preview is not available". Please advise what i'm doing wrong.

Thanks