Re: LTI authentication not working

I am totally stumped on my my LTI (External Tool) connections are not working. 

Here's the background, We are using moodle 3.6.2 version. Am attempting to connect to a set of courses using the external tool, as the LTI consumer.  The LTI publisher has provided me a series of courses, each with their own Cartridge URL and secret.  We are making up our own Consumer Key. 

When I take one of these cartridge urls and it's respective secret and I add it as an activity to a course, selecting external tool, I get the following error message: 

An error occurred when launching the external tool:Sorry, there was an error connecting you to the application.

The URL also changes and reads: 

https://learning.orionlms.com/mod/lti/return.php?course=542&launch_container=4&instanceid=74&sesskey=1YGqrzvLsN&lti_errormsg=Sorry%2C+there+was+an+error+connecting+you+to+the+application.&lti_errorlog=Debug+error%3A+OAuth+signature+check+failed+-+perhaps+an+incorrect+secret+or+timestamp.

Now, when I go over to the moodle sandbox site or even the moodle QA site, and load the cartridge and secret as an activity, using the external tool, I can access the course without any delay, no issues no problems.  What am I doing wrong? 

1 more test for you.  I published a course on my Moodle.  I went over to the Moodle Sandbox and Moodle QA site and loaded my own Cartridge URL and secret as an activity on a test course and I got the same response from the Moodle sandbox and QA site which was: 

An error occurred when launching the external tool:Sorry, there was an error connecting you to the application.

Now I know that the problem is our moodle...but what is it.  We have authorized the Plugin LTI feature for Authentication and Enrolment, so it's active.  But is there something else that we should be looking at or checking off?  Any and all help is gratefully appreciated. 

Thanks in advance,

Ken Kavanagh

Orion Learning

ken.kavanagh@orionelearning.com