From Canon USA:
Service Notice: Remote shooting with Camera Connect App with camera running Firmware Version 1.1.1
Thank you for using Canon products.
A communication error has been discovered when using the EOS 7D Mark II running Firmware Version 1.1.1, which version was released on April 27, 2017, in combination with the Wi-Fi Adapter W-E1.
We sincerely apologize for any inconvenience caused to customers, and we ask for your ongoing patience.
Remote shooting with the Camera Connect App is not possible after connecting the EOS 7D Mark II to a smartphone via the Wi-Fi Adapter W-E1.
EOS 7D Mark II Digital SLR Camera: Units that have been updated from Firmware Version 1.0.5 or earlier to Firmware Version 1.1.1
*This phenomenon will not occur if the camera meets either of the two conditions below:
We are currently making preparations to correct this phenomenon with the release of a firmware update in early June. In the meantime, please use the workaround method described below.
If you have not already done so, please register the EOS 7D Mark II. By registering, we will be able to notify you via email about future announcements.
This information is for residents of the United States and its five territories only. If you do not reside in the USA or its five territories, please contact the Canon Customer Support Center in your region.
Customer Support Operations
Canon U.S.A., Inc