Why has my Mac stopped seeing my S6?

[AC Question]

I'm running El Capitan on my Mac Air.

I've had no problem transferring photos up until now. Hook up the USB, Photos opens and asks if I want to import. Bing, done.

Today Photos doesn't open automatically. I opened it manually to see if it would ask about importing; it didn't.

I checked "about this Mac/System information". The Mac doesn't appear to see that the Android is connected via USB. But it is. The Android is charging because it's hooked up.

I've tried four different cords. Same result.

I downloaded the updated Samsung Switch. I've opened it several times, and plugged in the Android when told to. I've had two results: sometimes it didn't see the connection at all. The other times it tells me this kind of connection isn't supported, and to "change connection mode to media device". I have no idea what that means.

I know there are various other ways to send photos - File Transfer, etc. Every single one of them has detractors (I've been reading to forums for quite a while trying to find an answer).

What I want is to get back to where my Mac immediately and happily responded to seeing my S6 hooked up.

I've downloaded several updates in the past two days. Maybe one of those is the problem. I can't find a way to see which apps have updated. Any way to check that out?

If the problem isn't the updates - an idea why this has stopped working, when it was fine yesterday?

I appreciate any input. I'm not a computer/systems whiz, so the simpler the language you use, the better.

 

[Eternal Newbie]

Addendum: I've been on the phone with both t-mobile and Samsung.

T-mobile had me try downloading a driver. Turns out they don't have a driver for Mac.

Samsung's "advanced tech support" (one level up from the first layer) had no idea why it's been working all along with the Mac - he said it shouldn't have. He wasn't forthcoming about the latest updates. (T-Mobile said there's no way to see which apps have updated lately.

Alternatives:
I updated Samsung's Smart Switch. It can't see my phone either. (The phone is plugged into the USB port and functioning as a media device.)

While on the phone with Samsung, I downloaded Android File Transfer - which also can't see the phone.

Right now I'm moving files between my phone and my Mac via Dropbox, but that process is absolutely glacial.

Awaiting your wisdom.

 

[angel_kaye13]

So, I realize this problem may've already been solved (this forum is a year old, almost). But I was having issues, and browsing here and elsewhere.

I went ahead and downloaded the android file transfer, and I started to follow directions from another source: open settings>storage> then ...

Except no "..." was anywhere on my phone. (I have a Galaxy S6 edge.) But I was supposed to be looking for something like "USB connection." So I typed that in, and my phone brought up some usb options. I chose "USB configuration," which pulled up various options that my phone could configure as. The article I was looking at said to look for "MTP (Media Transfer Protocol)," which was on the list, so I chose that.

The Android File Transfer app opened automatically after that, and I was able to easily drag and drop my files onto my phone.

I hope this was helpful!