Unable to delete network connection (network view)

Hello all,

I'm sometimes unable to delete a connection-terminal in the network view, forcing me to delete the entire project and start a new one.

It is grayed out and not responding to delete actions (print screen in attachment).

Deleting the entire program also doesn't change a thing.

What is happening?

Program Version:     V8.1.0
Program Timestamp:     2016-07-15 08-49
Language Used:     en_US
Language Version:     8.1
Updates:
OS Name:     Windows 7
OS Version:     6.1
Processor:     amd64

I added the project.

You may need to change the extension to .7z depending on your unzipper.

The right s7 connection I just created trying to reproduce that undeletable connection.

I also don't now were that IP from the left connection came from.

The connection created itself at some point, after I Uploaded (LOGO1 > PC) HWsetting, diagram data and changed some programming in the diagram.

I've forwarded the issue to Support.