Hi Sivaraman,
Based on your description, the problem is related to the Office client. Since our forum focuses on Office 365 cloud services, for the Office 365 client related problems, I suggest you post a new thread on our Office forum for dedicated support. Thanks for your understanding.
Additionally, I’ve searched that forum and found two threads about similar issues. For your reference:
http://answers.microsoft.com/en-us/office/forum/office_2013_release-excel/files-not-opening-in-excel-2013/afdf3ff9-a3ca-435a-babb-fa29acf3ce11
http://answers.microsoft.com/en-us/office/forum/office_2013_release-excel/double-clicking-excel-file-takes-a-long-time-to/bf9ad77e-7497-4d50-b333-31fc2ca1877f
Regards,
Jerry