We have been using Sage 50 Pro Canada 2015 for a long time. Does the job. I had activation issues after setting up a new laptop. At one point, support suggested I try installing version 2025 (which didn't work.)
While I was dealing with setting up the new laptop. I still had the old one that had the 2015.3 version working. In all my trials, I'd also tried installing 2025 on that laptop on 13 Dec (but it still didn't work.)
I continued using that laptop to do the monthly bookkeeping (still on 2015.3) and the last time I used it was 30 Dec.
Today, suddenly, when I try to open the company file I've been using for weeks on the old laptop, with the 2015.3 version, it suddenly says that the file has been updated to a new file format and is not compatible with this version of the software. I opened the .SAI file with notepad and it says the file is for version 2025!
Now I can't open the file at all. Of course my last backup was two months ago. I don't understand how the file was updated to 2025 when I didn't do anything to it?
Is there anything I can do to restore the company? I just want to continue using it in 2015.3.