I'm having my share of programming fun over here, too.
I am using Access as a front end interface to MS SQL Server. I found a way to upload an Access table from the user's computer into a local temporary table on the server. This is a query that executes on the user's computer.
Side note: in MS SQL Server a local temporary table is only visible to the user who created it. After the end of the user's session this table is deleted. If created within a stored procedure, it is deleted when the procedure terminates. This is extremely helpful in multi-user systems. If a stored procedure needs to make a temporary table, but two people are using the same stored procedure, local temporary tables do not interfere with each other and they are automatically deleted when they are no longer needed. Local temporary tables can also be used as the equivalent of a print job in a queue. One user's job will not interfere with another user's job, and there will be no old rubbish tables cluttering up the schema.
It worked fine in Access 2010. It also works in Access 2016. So, what's the problem?
Access 2016 will not allow me to save the query; it only gives me an error message. Even in the old projects developed in Access 2010, this functions perfectly but I cannot open the query and save it unchanged.
Now I have to use this trick for a new project. I cannot even copy-paste the functioning SQL code from the query in the old project; Access will not allow me to save it.
My best guess is that Access 2016 added some error checking when queries are saved, and what it identifies as an error is anything but.