KodeKloud - Video Playback Troubleshooting (DRM-enabled videos)

Short summary: Follow the Simple Fixes first. If the video still will not play, collect the diagnostics listed here and open a ticket with support so we can escalate to Vimeo.

What is DRM and why it matters

DRM stands for Digital Rights Management. When DRM is enabled on a video it enforces usage rules set by the content owner and the hosting platform. Practically, that means the following common effects:

  • The video cannot be downloaded using ordinary 'download' controls or browser extensions.
  • Casting or screen capture may be restricted or blocked depending on device and OS rules.
  • Playback requires a healthy Content Decryption Module (CDM) on the browser or OS - examples include Widevine on Chrome/Edge/Firefox and FairPlay on Apple devices.
  • Playback may be blocked in certain regions if the content owner requested geographic restrictions.
  • DRM is not a guarantee of perfect playback everywhere - it increases security but also increases sensitivity to browser, OS, and network settings.
Bottom line: DRM prevents unauthorized saving and reuse of videos. It can introduce playback failures for users with outdated browsers, disabled CDMs, restrictive VPNs, or problematic local settings.

Who should use this guide

Any learner seeing a black screen, error message, or a video that will not start. Start with the Simple Fixes and only move to Advanced steps if you are comfortable collecting logs or if support asks for them.

Before you start - quick checklist

Support will ask for these items. If possible, note them before doing the advanced steps.

  • Course name and lesson name (or video hash from the lesson page).
  • When it happened (date and UTC time).
  • Device type and model (desktop/laptop/phone/tablet).
  • Browser name and exact version (for example: Chrome 123.0.5678.90).
  • Screenshot of the player area showing the problem.

Simple fixes - do these first

  1. Reload the page and try again.
  2. Close and fully restart your browser.
  3. Open the lesson in an incognito or private window and try the video.
  4. Try a different browser (if you are on Chrome try Edge or Safari).
  5. Reboot your device if the issue persists.

Why these work: Most playback issues are caused by transient state, extensions, or an outdated CDM. These basic steps clear state and disable extensions temporarily.

Browser-specific checks

Chrome and Edge (Widevine)

  1. Update Chrome or Edge: Menu - Help - About, let the browser update and restart.
  2. Update Widevine CDM: open chrome://components/, find Widevine Content Decryption Module and click "Check for update", then restart the browser.
  3. Turn off hardware acceleration to test: Settings - System - Use hardware acceleration when available. Toggle it, restart the browser, and test again.
  4. Clear site data for kodekloud.com and reload the lesson.

Safari (macOS and iOS)

  • Keep macOS and iOS up to date. Apple uses FairPlay DRM for Safari and iOS devices.
  • Check system privacy and screen-capture permissions. Some OS-level permissions can interfere with DRM playback.

Firefox

  • Ensure Firefox allows the Widevine plugin and that plugin updates are enabled: Settings - Extensions and Themes - Plugins. Restart after updates.
If after these checks the player still fails, collect the diagnostics described in the Advanced steps and attach them to your support ticket.

Common causes and what to try

  • Outdated browser or CDM: update and restart.
  • Extensions: test in incognito to rule out blocking extensions or ad blockers.
  • Hardware acceleration: toggle off and retest if you see a black screen with audio.
  • VPN, corporate proxy, firewall: try from a home network. Some corporate networks block DRM endpoints.
  • Region restrictions: DRM plus content owner settings can block playback in some geographic locations.

Advanced troubleshooting - collect diagnostics

These items are required if support needs to escalate the issue to Vimeo. If you are not comfortable doing this, open a support ticket and request help from a support agent.

A. How to record a HAR file (Chrome or Edge)

  1. Open the failing lesson page in the browser.
  2. Right-click anywhere and choose Inspect to open Developer Tools.
  3. Switch to the Network tab.
  4. Check the "Preserve log" option, then reload the page and reproduce the problem.
  5. Right-click in the Network panel and choose "Save all as HAR with content" or "Export HAR". Attach that file to the ticket.

B. Capture browser console logs

  1. Open Developer Tools and click Console.
  2. Reproduce the issue and copy error lines or take a screenshot of the console output.

C. Exact environment details to copy into the ticket

Browser: Chrome 000.0.0000.00
OS: Windows 10 21H2 or macOS 13.4.1
Device: Lenovo T14 / MacBook Pro 2019
Course: 
Lesson: 
Video hash: 
Timestamp: 2025-09-05T14:23:00Z
Steps to reproduce: Open lesson -> Click Play -> Error observed

D. Screenshot or short screen recording

Include the browser URL bar and the player area so we can see any error messages and the page context.

How to contact KodeKloud support

Email support@kodekloud.com with the information below. Add the attachments described earlier.

Suggested subject

DRM playback issue - CourseName - LessonName - BrowserName Version

Suggested ticket body - copy and paste

Hello support,

I am getting a playback error for a DRM-enabled video.

Course: 
Lesson: 
Video hash: 
Device: 
OS: 
Browser: 
Timestamp (UTC): 
What I tried: Reloaded, tried incognito, tried another browser, rebooted device.
Attachments: HAR file, console log screenshot, player screenshot

Please help escalate if the issue persists.

Thanks,

What KodeKloud support will do

  1. Confirm that you tried the Simple Fixes. If not, ask you to try them.
  2. If you attached HAR and logs, support will attempt to reproduce the issue on the same OS and browser version.
  3. If reproduction is successful or logs point to a backend issue, support will escalate to Vimeo with the HAR, console logs, and environment info to request backend blocked-playback reports.

FAQ

Q: The video is black but audio plays. What should I do?

A: Turn off hardware acceleration in your browser settings, restart, and test again. If that does not help, produce a HAR and console log and contact support.

Q: Can I download the DRM video?

A: No. DRM prevents ordinary downloads and blocks playback through some capture or download tools. If you need offline access for legitimate reasons, contact support to discuss authorized options.

Q: Will DRM block my ability to cast to a Chromecast or Apple TV?

A: Possibly. Casting and external display rules depend on the OS and device. Some devices block casting when DRM is active. If casting worked before and stopped after DRM was enabled, collect logs and contact support.

End-to-end summary and clear actions

If you see a playback failure:

  1. Run the Simple Fixes (reload, restart browser, incognito, try another browser).
  2. If the problem persists, run the Browser-specific checks (update browser and CDM, toggle hardware acceleration, test without extensions).
  3. If still failing, collect diagnostics (HAR file, console logs, screenshot, environment details) and email support at support@kodekloud.com with the suggested ticket body and attachments.
Clear action for users now: Try the Simple Fixes and then email support with the HAR and logs. Doing this will get you the fastest resolution.

Three point final summary

  • Start with the Simple Fixes: reload, restart, incognito, and try another browser.
  • If those fail, update the browser and CDM, and toggle hardware acceleration off for testing.
  • If still broken, collect HAR and console logs and open a support ticket with the attachments. Support will escalate to Vimeo if needed.