I'm trying to upgrade from Sage50 2017 to Sage50 2019 version. I am able to install the new version but when I try to upload the data from my backup it comes up with an error 

I reviewed my error log and the log it has this statement

Problem with table <tempdd>: Incorrect information in file: '.\simply\tempdd.frm'

I looked for this file in my .SAI folder and it appears to have no value ie 0KB.

Would appreciate help on how to fix this problem.