add notes on upload failures and recovery

user_manual/android_app.rst

@@ -108,7 +108,12 @@ The ownCloud menu at the top left shows the name of the logged-in user, has a
 shortcut to your files, the **Uploads** button, and the **Settings** button.
 
 The Uploads page displays the status of files currently uploading, a list of 
-your recently-uploaded files, and a Retry option for any failed uploads.
+your recently-uploaded files, and a Retry option for any failed uploads. If 
+credentials to access the file have changed, you'll see a credentials error. 
+Tap the file to retry, and you'll get a login screen to enter the new 
+credentials. If the upload fails because you're trying to upload to a folder 
+that you do not have permission to access, then you can select a different 
+folder.
 
 .. figure:: images/android-15.png
    :alt: Top-left menu.