The FaceTime preferences is greyed out, how do I correct so I can login to FT

I went through the steps very carefully.

I don't understand 'log out' and 'log in'. In and out of what?

iMessage? Facetime?

I'm still getting this, for the last 10 minutes

and now, how to remember which files went where... :-(

Hi,

none of these steps worked for me. I'm still not able to log in Facetime. Do you have any hint on what is going on and how to solve it?

I'm using a 2015 macbook air 13.3'', updated today to macOS high sierre, although the problem was there since before the update.

If the FaceTime window opens with a white camera icon with a slash through it on a black background, that means it can't find a camera. Without a camera, it won't work. Follow the instructions in this support article.

Otherwise, I suggest you take each of the following steps that you haven't already tried, stopping when the problem is resolved. Back up all data before making any changes.

Step 1

If the FaceTime window shows that it's turned off, turn it on.

Step 2

Launch the Messages application and sign in to your iMessage account. If you get an error message, stop here and post the complete, verbatim text of the message.

Step 3

Make sure you know the ID and password you use with iMessage. Launch the Keychain Access application in any of the following ways:

☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

☞ Open LaunchPad and start typing the name.

Use the search box in the toolbar of the Keychain Access window to find and delete all items with "iMessage," "FaceTime," or "Apple Persistent" in the name. Log out and log back in.

Step 4

Hold down the option key and select

Go ▹ Library

from the Finder menu bar. Move the following items from the Library folder to the Trash (some may not exist):

Caches/com.apple.Messages

Caches/com.apple.imfoundation.IMRemoteURLConnectionAgent

Containers/com.apple.FaceTime

Leave the Library folder open. Log out and log back in. Try FaceTime again. If it works now, stop here. Close the Library folder.

Step 5

In the Preferences subfolder of the Library folder, there may be several files having names that begin with any of the following strings:

com.apple.FaceTime

com.apple.facetime

com.apple.ids

com.apple.imdsmsrecordstore

com.apple.imessage

com.apple.imservice

Move them all to the Desktop. There may also be a file with the name "com.apple.imagent.plist". Move that to the Trash.

Also in the Preferences folder, there's a subfolder named "ByHost". Open it and do the same thing.

Log out and log back in. Test again. If FaceTime now works, you may optionally be able to put back some of the files you moved to the Desktop in this step. Relaunch and test after each one. Eventually you should find one that causes FaceTime to malfunction. Delete those files and recreate whatever settings they contained.

If the issue is still not resolved, quit FaceTime and put all the items you moved to the Desktop back where they were. You don’t need to replace the items you moved to the Trash.

If you get through all the above steps without a resolution, post your results.

OMG! Facetime opened! You're a genius David, thank you.