# Error reading 'caps' when joining meeting

**URL:** <https://devforum.zoom.us/t/error-reading-caps-when-joining-meeting/137733>\
**Category:** Meeting SDK\
**Created:** [September 30, 2025, 1:55am UTC](https://devforum.zoom.us/t/error-reading-caps-when-joining-meeting/137733 "2025-09-30T01:55:51Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![andrew.hsu1](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/andrew.hsu1/32/50828_2.png) [@andrew.hsu1](https://devforum.zoom.us/u/andrew.hsu1)\
**Post date:** [September 30, 2025, 1:55am UTC](https://devforum.zoom.us/t/error-reading-caps-when-joining-meeting/137733/1 "2025-09-30T01:55:51Z")

</div>

**Meeting SDK Type and Version**  
Type: Web  
Version: 4.0.7

**Description**  
Error reading ‘caps’ at lM.getLocalRecordingPermissionUserList

**Error?**  
I’m intermittently getting errors about a runtime issue:  
Cannot read properties of undefined (reading ‘caps’)  
at lM.getLocalRecordingPermissionUserList. Note, this error doesn’t always prevent me from successfully having a meeting-- after dismissing, the meeting seems to be working sometimes.

Here is the error:

```auto
Cannot read properties of undefined (reading 'caps')
TypeError: Cannot read properties of undefined (reading 'caps')
    at lM.getLocalRecordingPermissionUserList (http://localhost:4200/vendor.js:71193:27432)
    at http://localhost:4200/vendor.js:71382:672597
    at http://localhost:4200/vendor.js:71196:53857
    at Array.forEach (<anonymous>)
    at Object.next (http://localhost:4200/vendor.js:71196:53845)
    at e.next (http://localhost:4200/vendor.js:71187:52215)
    at t._next (http://localhost:4200/vendor.js:71187:51885)
    at t.next (http://localhost:4200/vendor.js:71187:51534)
    at http://localhost:4200/vendor.js:71187:67063
    at t.<anonymous> (http://localhost:4200/vendor.js:71187:66859)

```

**Troubleshooting Routes**  
I’ve read similar issues, although I can’t seem to find one that can help me resolve this. Even when joining with my host first, I’m intermittently getting this on my host machine

**How To Reproduce**  
Here is my code snippet, using the component instructions for the Web SDK:

```auto
  const joinMeeting = async (params: JoinMeetingParams) => {
    dismissVideoCallNotification();
    const meetingSDKElement = document.getElementById(
      params.elementId || 'meetingSDKElement'
    );
    let clientIsInitialized = false;
    try {
      const initializeResult = await client.init({
        zoomAppRoot: meetingSDKElement || undefined,
        language: 'en-US',
        patchJsMedia: true,
        customize: {
          video: {
            isResizable: true,
          },
        },
      });
      if (typeof initializeResult === 'string') {
        clientIsInitialized = true;
      }
    } catch (err) {
      console.error('Failed to initialize SDK:', err);
    }
    try {
      if (clientIsInitialized === false) {
        console.error('Zoom client is not initialized.');
        return;
      }
      await client.join({
        signature: params.jwtToken,
        meetingNumber: params.meetingNumber,
        password: params.password,
        userName: getFullName(params.user) || 'Plana Client',
        userEmail: params.user.email,
      });
    } catch (err) {
      console.error('Failed to join meeting:', err);
    }
  };

```

---

<div class="post-metadata">

**Author:** ![amanda-recallai](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/amanda-recallai/32/44747_2.png) [@amanda-recallai](https://devforum.zoom.us/u/amanda-recallai)\
**Post date:** [October 1, 2025, 3:12pm UTC](https://devforum.zoom.us/t/error-reading-caps-when-joining-meeting/137733/2 "2025-10-01T15:12:58Z")

</div>

Hi @andrew.hsu1, this is similar to a known Web SDK issue where the local-recording permission path throws **“reading ‘caps’”** when the host isn’t present yet or meeting metadata isn’t ready - see **[Error in mediaCapturePermission API: TypeError: reading ‘caps’](https://devforum.zoom.us/t/error-in-mediacapturepermission-api-typeerror-cannot-read-properties-of-undefined-reading-caps/96683)**.

If the error is **consistent** , it’s typically because the meeting allows join-before-host and the bot joined first; the permission request needs the **host in the meeting** to resolve, otherwise this exception is raised (documented in **[that thread’s accepted answer](https://devforum.zoom.us/t/error-in-mediacapturepermission-api-typeerror-cannot-read-properties-of-undefined-reading-caps/96683/7)**).

If you aren’t doing recording, skip the recording-permission helpers because the **[Web Meeting SDK does not support local recording](https://devforum.zoom.us/t/need-assistance-with-zoom-meeting-web-sdk-local-recording-feature/107270)**.

If you do need the compliance prompt, only call **[`mediaCapturePermission`](https://marketplacefront.zoom.us/sdk/meeting/web/functions/ZoomMtg.mediaCapturePermission.html)** after you’re fully in-meeting and the **host is present** , and guard for undefined state before reading capability fields.