"Operation must use an updateable query" error in MS Access

I had the same problem exactly, and I can't remember how I fond this solution but simply adding DISTINCTROW solved the problem.

In your code it will look like this:

UPDATE DISTINCTROW [GS] INNER JOIN [Views] ON <- the only change is here
    ([Views].Hostname = [GS].Hostname) 
    AND ([GS].APPID = [Views].APPID) 
 ...

I'm not sure why this works, but for me, it did exactly what I needed.

There is no error in the code, but the error is thrown due to the following:

 - Please check whether you have given Read-write permission to MS-Access database file.
 - The Database file where it is stored (say in Folder1) is read-only..? 

suppose you are stored the database (MS-Access file) in read only folder, while running your application the connection is not force-fully opened. Hence change the file permission / its containing folder permission like in C:\Program files all most all c drive files been set read-only so changing this permission solves this Problem.

Whether this answer is universally true or not, I don't know, but I solved this by altering my query slightly.

Rather than joining a select query to a table and processing it, I changed the select query to create a temporary table. I then used that temporary table to the real table and it all worked perfectly.

I had the same error when was trying to update linked table.

The issue was that linked table had no PRIMARY KEY.

After adding primary key constraint on database side and re linking this table to access problem was solved.

Hope it will help somebody.