LTI

The Main Problem Areas

• LTI not starting
  White screen, 404/500 errors, infinite loop, or redirection to the provider's login page

• Progress or completion is missing
  The external content has been completed, but the status or score is not updated in the imc Learning Suite.

• LTI 1.3 cannot be set up
  The required platform data is missing, or the feature is not available.

• User information is incorrect
  The provider does not correctly identify the learner or assigns the learner to the wrong account.

• Deep linking or content selection is not working
  External content cannot be selected or linked.

• Usage on mobile devices differs
  The launch works on the desktop, but not in the app or in a mobile browser.

Problem: LTI 1.3 is not Available or Cannot be Created

If LTI 1.3 is not available in your Media types administration function, this is often due to activation issues or requirements of your environment. Please check the following points before contacting the provider:

Typical Symptoms

• For external service providers, you can only select LTI 1.1.

• The External LTI 1.3 tool media type is missing.

• You may need to enable LTI 1.3 for your test or production environment.

Possible Causes

• LTI 1.3 is not enabled in this environment.

• TRequired license components are missing.

• The desired function is only available in a specific architecture or version.

How to Check Availability

1. Check whether External LTI 1.3 tool is available in the media types adminsitration.

2. Check whether the required LTI media type is available.

3. Check whether your environment has been enabled for LTI 1.3. If the option is missing, contact your Scheer IMC contact person.

4. If the option is not available, check the license and activation status internally.

If the LTI 1.3 option is missing, please contact your Scheer IMC contact person. Include the name of the environment and a screenshot of the available media types.

If LTI 1.3 is not Available

To set up LTI 1.3, you will need specific platform data from the imc Learning Suite. Always use the values from the same environment and enter them unchanged into the external tool provider.

Required Platform Data

• Client ID

• Deployment ID

• Issuer

• OIDC Login / Authorisation URL

• OAuth2 Access Token URL

• JWKS / Public Key Set URL

Where to Find the Values

Depending on your setup, you can find the required values in the LTI tool's configuration or obtain them from your Scheer IMC contact person. Do not use values from a different environment.

How to Set Up the Platform Data

1. Ensure that LTI 1.3 – and not 1.1 – is actually set up.

2. Check whether the platform data is visible once the tool has been set up, or whether it must be provided separately.

3. Verify that the provider expects the exact URLs and that stage and production values are not mixed up.

4. When changing environments, make a strict distinction between test and production.

Use only the corresponding URLs and keys for testing and production. Document which environment each value comes from.

If the LTI Launch Fails

The most common error is a failed LTI launch. Go through the following checks in the order listed and note at which step the behavior differs from the expected.

Typical Symptoms

• White screen or endless loading

• HTTP 404 or HTTP 500 after returning to the previous page or launch

• Provider login instead of directly accessing the content

• Signing off after a while

• Errors only in certain roles or channels

Common Causes

• Incorrect launch, login, or redirect URL

• Invalid signature or invalid authentication for LTI 1.1

• Cookies, SameSite rules or browser security mechanisms

• iFrame incompatibility on the provider’s side

• Role- or context-based differences between the backend preview and the learner view

• Unsupported behaviour in mobile apps or mobile browsers

Step-by-Step Check

1. Check whether the launch, login, redirect and JWKS/public key values match the provider’s specifications.

2. Check whether the provider supports iFrame embedding or requires new browser window.

3. Test the launch both embedded and in a new browser window.

4. For LTI 1.1, have the provider verify the signature and callback configuration.

5. If Deep Linking is used: Check whether, instead of the content, only a generic launch without any content context is being called up.

If Progress, Completion or Score are Missing

If an external course has been completed but the status in the imc Learning Suite remains unchanged, the cause is usually related to the provider's feedback or to the mapping of completion status and results.

Typical Symptoms

• Medium remains incomplete despite completion by the provider

• Course progress remains unchanged

• PASSED status is not returned

• Mastery score is set, but has no visible effect

• Response is significantly delayed

Common Causes

• Provider is not sending a valid completion/score callback

• Provider and LMS interpret ‘failed’, ‘completed’, or Score differently

• Incorrect Mastery score or inappropriate learning logic

• Technical error in the callback, such as a signature issue with LTI 1.1

• Expectation conflict between the behaviour of test media and LTI media

Recommended Test

1. Please confirm with the provider that the completion data is actually being sent back to the imc Learning Suite.

2. Check whether Completion, Passed/Failed and Score are supported in the LTI media you are using and are configured correctly.

3. Check the course's Mastery score and learning logic.

4. Determine whether the problem occurs at the media level or at the course level.

5. If there is a delay in the response, check whether the provider is actively pushing data or using delayed processing.

If User Data is Incorrect or Incomplete

The external provider uses the user information transmitted when LTI is launched for mapping. This information must be unique and conform to the expected format.

Typical Symptoms

• Provider can only see a technical ID

• Name or email address are not transmitted

• Email is transmitted even though only a pseudonymous ID is required

• Several learners share one email address, which causes conflicts

• Tutors or administrators are recognised as learners

Important Information on User Assignment

• If possible, use a unique user ID. Shared email addresses may result in duplicates or assignment errors on the provider's end.

• Providers often expect stable, unique identifiers.

• Role mapping does not automatically correspond to the expectations of the external system.

Recommended Test

1. Check with the provider which unique identifier should be used and whether email address, name and role are required.

2. Check whether email address, name or roles are actually required.

3. If possible, transmit only unique technical IDs.

4. Check whether the problem is limited to specific user groups or roles.

If the provider does not support shared email addresses, you will need a unique user ID or a custom mapping.

If Deep Linking or Content Selection isn't Working

Deep linking allows you to select and link to specific content from an external provider. If this function is missing, first check that it is supported and correctly configured on both sides.

Typical Symptoms

• The 3rd-Party Import menu item is missing.

• When selecting content, only the provider's login page appears.

• Links must still be maintained manually from CSV lists.

• When switching platforms, numerous existing content links must be replaced.

Recommended Test

1. Check whether deep linking is actually supported by the provider.

2. Check whether the function is available in the version and environment you are using.

3. Verify that the deep linking URL and the launch URL have not been mixed up.

4. When performing migrations, clarify early on whether bulk changes via a mapping list or script are necessary.

If Usage on Mobile Devices Differs

If LTI content works on the desktop but not in the app or in a mobile browser, it is often due to an embedding or session restriction.

Typical Symptoms

• LTI launches on the desktop, but not on mobile devices.

• SCORM and LTI display blank pages or errors in the app, while MP4 works.

• Mobile requests result in generic system errors.

Possible Causes

• Cookie and session limitations in a mobile context

• Unsupported iFrame or redirect flows

• Provider-imposed restrictions on embedded mobile usage

Recommended Test

1. Test desktop and mobile versions separately and document the device, operating system, browser and app version.

2. Check whether it is possible to open the page in an external browser instead of embedding it.

3. Check with the provider to see whether mobile and embedded use are officially supported.

Classifying HTTP Errors when Launching LTI

The HTTP status provides an initial indication of the cause. The exact meaning may vary depending on the external provider.

Browser and Network Check

If you experience launch issues, you can track the request in your browser. Open the developer tools by pressing the F12 key, select the Network tab, tick the Clear network log checkbox if possible, and relaunch the LTI content.

Document the following:

• Request URL and redirects

• HTTP status and error message

• Error in the browser console

• Browser, operating system and device

Common indications are blocked 3rd-party cookies, content security policy or CORS errors, iFrame embedding being blocked, mixed content or certificate errors. Also try opening the content in a new browser window. If it works there, the cause is likely to be related to the embedding or to browser security rules.

Comparative Tests for Narrow Down the Options

Compare the information as specifically as possible so that it is clear whether the issue affects users, a course, an LTI component or a provider:

1. Same user, same provider, different course

2. Different user, same course and same LTI component

3. Same user and course, different LTI component

If only one user is affected, check in particular the user ID, email address, role, permissions and the account with the external provider. If all users are affected, first check provider availability, environment settings, URLs, certificates and network restrictions. If only one course is affected, the cause is more likely to be related to the course or media configuration, or to the resource link.

LTI 1.3: Line Item and Assessment

In LTI 1.3, an assessment is assigned to a course and an LTI component via a so-called Line Item. If a score is available on the provider's side but is missing in the imc Learning Suite, verify that the Line Item has been created correctly and that the user has been assigned to the correct entry.

When submitting a request, please ensure you include the following information:

• Line Item description and maximum number of points

• Points transmitted and time of transmission

• Activity status: started, in progress, submitted, or completed

• Assessment status: not ready, pending, fully assessed or failed

The presence of a score does not automatically mean that the content is already considered complete. Activity and assessment statuses must be set according to the external provider's configuration and the desired course logic.

If there are no assessments, ask the external provider to confirm that the score or completion callback was actually sent. If possible, ask them to provide the time and a Request or Correlation ID.

Information for the Initial Analysis and Support Request

A single error scenario, as recent as possible, is most helpful for the analysis. Please first conduct a brief comparison test and, when submitting a support request – if permitted – provide the following information.

Quick Check

Before creating a ticket, please check the following:

• Is it version LTI 1.1 or LTI 1.3?

• Are the LTI settings configured for the respective environment aligned with those of the external provider?

• Is it possible that the test and production system were connected using different or incorrect configuration values?

• Does the problem only occur when embedding in the iFrame?

• Does the problem only occur on mobile devices or in the app?

• Are only individual users, courses or LTI components affected?

• Are the user ID, email address, and role transmitted in the format expected by the external provider?

• Do other LTI content from the same provider work?

• Is a completion or assessment displayed correctly with the external provider?

• Is it specifically about:

  • launching the LTI content,

  • user mapping,

  • deep linking,

  • completion,

  • or the transmission of a assessment?

Information Required for Scheer IMC Support

Create a HAR file using Chrome or Firefox

A HAR file records network communication during a failed call. Create it only for the specific error instance and send it exclusively via the designated secure transmission channel.

Google Chrome

1. Open the Developer tools using the F12 key or via ⋮ > More Tools > Developer tools.

2. Select the Network tab and enable the Clear network log checkbox.

3. Delete existing entries using the Delete network log icon.

4. Launch the LTI content again and wait for the error to occur.

5. Right-click in the list of network requests and select the Save all as HAR with content option.

Mozilla Firefox

1. Open the Developer tools using the F12 key or via ☰ > More Tools > Browser Tools > Web Developer Tools.

2. Open the Network tab, click on the Network Settings gear icon top right and select the Persist Logs option.

3. Clear the log using the Clear trash can icon, relaunch the LTI content and try to reproduce the error.

4. Right-click in the list and select the Save All as HAR option.

Along with the HAR file, please include the exact time the error occurred, the time zone, the browser used and the affected platform URL.

Please provide the following information if possible:

Environment and Integration

• Platform URL

• Production or test system

• LTI version

• Name of the external LTI provider

Affected Content

• Course name

• Name of the LTI component

Users

• the affected user or an anonymised unique user identifier

• Email address only if it is required for the analysis and its disclosure is permitted

Error

• Exact date and time, including time zone

• full error message

• HTTP status (if displayed)

• Screenshot

• expected behaviour

• actual behaviour

• Browser and browser version

Scope of the Problem

Please indicate whether the problem concerns

• a user

• several users

• all users

• a course

• several courses

• an LTI component

• some or all of the content from the same provider.

If possible, please also provide a working example for comparison.

Technical Analysis

In the event of launch, redirect or HTTP issues, Scheer IMC Support may also request a HAR file of the failed request.

Please always include the exact time at which the error was reproduced along with the HAR file.

Privacy and Confidential Data

Please do not send any passwords, Shared Secrets, private keys or other credentials in a support ticket.

Confidential data should be masked. Personal data should only be transmitted if it is necessary for the analysis and permitted under your organization’s guidelines.

For sensitive files and information, use only the secure transmission channels provided by your organisation.

When is Support Needed?

Example of a Helpful Support Request

Instead of:

LTI isn't working.

If possible, please:

The user max.mustermann accessed the LTI content ‘Compliance Training’ in the course ‘Compliance 2026’ on 11 August 2026 at approximately 2.32 pm.

The message ‘401 Unauthorised’ appears.

The problem also occurs in another browser and affects several users.

Other media work without any problems.

A screenshot and – if requested – an HAR file of the failed request are attached.

The more precisely the specific error is described, the faster the cause can be identified.