Hi Jan Hardie, 

Thanks for reaching out. Here's a resource that might help, section 4 part 4 in particular reads:

"If you have multiple fiscal periods to download, you will get Error: "The date must be between ##/##/### and ##/##/###. If you want to process transactions in the next year, choose Start New Year or Change Session Date from the Maintenance menu to start a new year."

• This is normal and starting a new year resolves this issue
• Before starting a new year in Sage 50 in a (newly created data file only), verify that the financials in SBCA match Sage 50's financials
• Verify with accountant as needed
• To start a new year in Sage 50, see KB 36175 Video: How to start a new fiscal year

For additional assistance, you can also reach out to:

Sage Expert Services

• Sage Expert Services is able to perform the migration service activities in this article
• Additional costs do apply and are not included in your regular Sage 50 support plan
• To save time, you can setup an appointment with a Sage Expert Service member - Connect with a Sage 50 expert via online scheduler - Click Here and a member of the Sage Expert Services team will contact you

Hope this helps!

Warm Regards, 
Erzsi