Error: 'The given key was not present in the dictionary.' when connecting to or selecting a table in an Oracle database, after installing .NET 4.6. (4234605)

After installing .Net Framework 4.6 or Visual Studio 2015 (which installs .NET 4.6), when trying to connect to an Oracle database, to select a table in the database or to publish a snapshot to Toad Intelligence Central, the errors below appear.  It does not affect connection to MySQL databases.

1)

'System.Collections.Generic.KeyNotFoundException'
The given key was not present in the dictionary.

2)

3)

System.ComponentModel.Win32Exception
Proxy process has gone away

WORKAROUND 1:
Install and use a 32-bit Oracle Client instead of a 64-bit client. Ensure the 32-bit client is selected in the right-click a saved connection | Properties | 'Current Home' drop-down box.

WORKAROUND 2:
Uninstalling .Net Framework 4.6 fixes the issue.  Ensure that .Net Framework 4.5 is still installed in the PC.  NOTE:  .Net 4.6 can be auto-installed or auto-updated back in the PC.

WORKAROUND 3:
Upgrade to the latest version of Toad Data Point, which can be downloaded here.

STATUS:

Issue is fixed in version 3.8.1. The latest version of Toad Data Point can be downloaded here.