Brother, I would recommend NOT trying to use a hyperlink field. Those are a pain. Here is a function that will prompt the user for selecting a folder in Windows. this isn't the EXACT code that I used for many years but it should do the trick.
Dim sFolder As String
' Open the select folder prompt
If .Show = -1 Then ' if OK is pressed
sFolder = .SelectedItems(1)
If sFolder <> "" Then ' if a file was chosen
' put your code in here
From: VBA Select Folder with msoFileDialogFolderPicker - wellsr.com
To be honest, I had an API call that I prefered to that method but I'm having trouble finding it, it's been a few years. This msoFileDialogFolderPicker is probably a safer method, then to trust random people online who give you API code to call. Cheers ,I hope that it helps.
and then on the OTHER side of the equation, if you do NOT use a hyperlink field, and if you need a button next to the field that will open that form, I think that you just call this code
Dim strShell as String
strShell = "EXPLORER.exe " + CHR(34) + me.folderPath + CHR(34)
I'm pretty sure that will 'Open' the folder for the user, I hope that is what you are talking about, and I think that will do everything that your intention to use a Hyperlink will accomplish.
Now, if you want to display the FOLDER and have the user choose a file, THAT is something else entirely.
I haven't posted anyting on Access Forums for many years... Because I'm a known TROLL who is still PISSED that Microsoft killed off 'Access Data Projects'. Those were MUCH better solution than JET databases as they support stuff like Replication, Realtime Backups, Log Shipping, Auditing.
Damnit I wish that Office 2010 would still actvivate, because today, I'd still be using ADP if it still functioned. but Access 2019 is pretty slick.. they have fixed a couple of things over the years that make Access Databases a lot more acceptable, for example BIGINT support in linked tables. Cheers, and I hope that helps.