I added an iPad to my collection of devices that have my msecure data. For syncing, I switched from iCloud to mSecure Cloud. When I made the switch I received the message: 'Cannot modify user [text string]'.
So I tried to revert back to iCloud but still receive the error: 'Cannot modify user [text string]'
So now I'm stuck - connected (I think) to mSecure Cloud on my main machine (with the mS data) and connected to iCloud syncing on my iPad. I'm unable to make any progress as the main machine reports the error with anything I try to do.
I can't go forward and I can't go backward to restore previous configuration.
Current state: My current devices (MacBook Pro and iPhone) appear to be isolated from one another, each with their own data. My new device (iPad) is installed but has no data and no connection to the other devices.
I responded to the issue you're experiencing in a different thread. If you want, you can respond to this one that you created, or go ahead and respond to the other one. From here on out, we'll just keep the correspondence in the one thread you choose to respond to.