How do I access my encrypted memory card now?

I just installed the latest update (on 6 July 2018) and now it's saying that the data on my memory card can't be read. It says I have to decrypt it on the system that encrypted it which is the phone I'm currently using. Can someone help with this?

Welcome to Android Central! Which phone? Was it an official system update pushed over-the-air, or did you flash it manually?

It's a S7 Edge. It was an official update.

It didn't act like a factory reset, right? That is, you didn't have to go through the whole Setup Wizard after the update?

Were you using the SD card as portable storage, or had you done that ADB hack to enable Adoptable Storage?

No factory reset. Yes, I was using it as portable storage. No hacks done to the phone.

What if you remove the card and insert it into your PC? Is it unreadable there due to encryption as well?

It was the first time. It's working now. Thank you. I can finally get my photos back.

Or not. The photo files can be found, they just can't be opened now.

First, look at photos.google.com. If they're there, they're not lost. If they're not there, restart the phone. If that doesn't make them readable, try turning the phone off, then turning it on. Try using - using Google Photos to see them.

If they're still not readable, make sure that photo backup (in Accounts/Google/<your google account>) is enabled, then check photos.google.com again.

If you still can't see them, consider them lost. In the future, when you take pictures, back them up to your Google Drive account.

Using an SD card as internal storage is intended to be a stopgap measure to enable you to install more apps only until you can get a larger phone - it's like a cheap spare tire that lets you get to the station to get the real one fixed. Never depend on an SD card as the only storage for important files.