File Size causing issue when saving the Excel File to SharePoint

I am trying to save Excel 2010 to SharePoint 2010 library. I do this from Excel, File-->Save & Send-->Save to SharePoint and saving it to the desired SharePoint library. This works ok if the file size is small. If the file size is more than 5 MB then i am getting an error "This file contains document properties that have failed custom  validation".

Dont go by this error, it is mis-leading. I am able to save the same file to SharePoint library if I reduce the file size by deleting some of the attachments.

Also if i upload the file manually directly from SharePoint site, it is working ok even if the file size is more than 10 MB.

Another point is, I am not facing this problem if i use my test SharePoint site.

Any help is much appreciated!! Thank You!!