Anything that is a text datatype needs quotes around it whereas numeric data types do not. So if Me.Main_Folder equals 'MyFolderName' then the [Folder Name] parts looks something like:
[Folder Name] = 'MyFolderName'
What you had there should have actually worked. It was the numeric [Programme ID] part that you put quotes around which caused the error and it didn't need the quotes. So that part needed to look something like:
[Programme ID] = 1234
In your code that errored that part evaluated to something like:
[Programme ID] = '1234'
Hope that makes sense -