Authentication failing for iCloud

[Ilfracombe]

Up until last night, I had no problem with getting my iCloud account on aquamail. Now, today, I consistently get a message saying authentication failed.
This is on a Nexus 5
I checked password, etc, and they are all correct, nothing has changed.
I am able to connect with icloud mail using Google Mail, authenticate and download messages.

The only thing that has changed since last night and this morning is that I upgraded iOS on my iPhone.
Might this problem be connected with two-factor authorization?

[Kostya Vasilyev]

The only thing that has changed since last night and this morning is that I upgraded iOS on my iPhone.
Might this problem be connected with two-factor authorization?

No idea, really, sorry. To me iCloud is just like any other IMAP / SMTP mail service.

Could the iOS upgrade "do something" to the account's "security settings" (making a guess here)? Since iCloud accounts are "special" to iOS as much as Gmail accounts are "special" to Android?

Can you try turning off two factor, to see if it helps?

In general, for two factor (this is not iCloud specific) it's necessary to generate an "app specific password" and use that instead of the "master" password.

[Ilfracombe]

I turned off two-factor authentication and now Aquamail can get the mail again, as before.

But I'd like to use two-factor authentication, so now what?

[Ilfracombe]

I went back to two-factor authentication of iCloud to see if Aquamail can now work with it.

It doesn't, I'm afraid. If there's something I should do, I don't know what it is.

Tim

[mikeone]

In general, for two factor (this is not iCloud specific) it's necessary to generate an "app specific password" and use that instead of the "master" password.

Kostya:
In general it's not clear to me how a "app specific password" can be generated when "two-factor authentication" is in use.

[Kostya Vasilyev]

Let's see:

https://www.google.com/search?q=icloud+app+specific+password

First result for me:

https://support.apple.com/en-us/HT204397

In general, this is not Apple or Aqua Mail specific:

Step 1 - go to the mail provider's web site and generate an app specific password for Aqua Mail (or "an app")

Step 2 - use it in Aqua Mail (or "an app") instead of the account's "real" password

PS - had Apple supported the standard OAUTH2 authentication method, we could add it in Aqua Mail (as already done for Gmail, Hotmail and Yandex). And then the above "extra steps" won't be necessary. But iCloud doesn't support OAUTH2 it seems.

[mikeone]

Kostya:
Many thanks for your useful explanations.