When the user(s) attempt to use SmartLists, what are they seeing?
The SmartLists are held in tables in the DYNAMICS/system database for Dynamics GP, such as ASIEXP81, ASIEXP83, ASIEXP86 and others, so it's rare that we would lose the SmartList reports, as there shouldn't be anything, even during an upgrade, deleting data from these tables.
That being said, one thing we do frequently see, is that a customer will have SmartList reports that they created in SmartList Builder, but then in the new version of Dynamics GP, they do not have SmartList Builder installed, thus the reports created in SLB are not available to them.
One way to determine this is to look in the ASIEXP81 table, which is the SmartList Favorites Master table, and using the ASI_Favorite_Name column, find the name of the SmartList report that isn't working, then look at the ASI_Favorite_Dict_ID column to see what value that shows.
If ASI_Favorite_Dict_ID shows 3830, that is the product ID for SmartList Builder which, after GP 2013 R2, is solely owned and supported by eOne. If you do see reports for the 3830 dictionary ID, you'll then want to verify whether or not SmartList Builder is installed for the Dynamics GP application being used or not.
For default/canned SmartList reports, if they are truly missing for some reason, we can get scripts to get those back, but for any custom SmartList reports or favorites, you'd need to find a backup of the DYNAMICS/system database for when those reports still existed, and use some type of DTS to get the missing data back, as needed.
To answer the other questions, it's possible that even after re-creating users with the same name and password in Dynamics GP, the users may lose their home page settings, especially if the users were deleted from Dynamics GP before they were re-created again.
Let me know if you have any questions.
Thanks