When the Zoom app shows Error Code 104105, it signals a connection failure between your device and Zoom services. The quickest path to resolution is to confirm the network route is open, then verify the app and device settings are not blocking secure traffic.
This guide stays focused on causes, diagnosis, and steps that directly affect Zoom connectivity. It applies to home networks and managed corporate environments.
Table of Contents
What Error Code 104105 Means
Error Code 104105 is commonly tied to connectivity issues where the client cannot reliably reach Zoom servers. Zoom groups this code with other server connection errors in the same family, and recommends checking firewall and proxy conditions first.✅Source
Typical signs include a stuck connecting state, a join attempt that fails immediately, or a meeting that starts to load and then stops. The goal is to determine whether the issue is caused by Zoom service availability, your local network, or a device-level filter such as security software.
Causes and Common Triggers
Error Code 104105 is most often caused by one of these traffic-path blockers. Each item maps to a different fix, so it helps to identify the exact trigger early.
- Firewall rules blocking outbound Zoom traffic, especially meeting ports needed for media.
- Proxy or secure web gateway behavior that disrupts TLS sessions or forces authentication in a way the app cannot complete.
- SSL inspection that interferes with Zoom’s encrypted connections.
- VPN routing that introduces packet loss, unstable paths, or blocked regions inside a managed network.
- DNS resolution problems that prevent the client from finding the correct Zoom endpoints.
- Local security software that blocks or sandboxes Zoom processes and prevents network access.
Fast Checks That Save Time
Run these checks in order. They separate service-side events from local network constraints with minimal effort.
- Check Zoom’s status page for incidents or maintenance affecting meetings, login, or related services.✅Source
- Confirm you can open zoom.us in a browser on the same device. If the site fails, focus on DNS, firewall, or gateway filtering.
- Try a different network (mobile hotspot is enough). If it works there, your primary network is the constraint, not your Zoom account.
- Temporarily disconnect VPN and retry. If the error disappears, keep the VPN off for Zoom or ask for a split-tunnel exception.
If the error happens only on one device, focus on local settings, the Zoom app version, and endpoint security. If multiple devices fail on the same network, focus on firewall, proxy, and port access.
Network Rules Zoom Usually Needs
Zoom meetings depend on a mix of TCP and UDP. TCP often handles signaling and session setup, while UDP is preferred for real-time media. If your network blocks the required ports, Error Code 104105 is a common outcome.✅Source
| Category | What To Allow (Outbound) | Why It Matters |
|---|---|---|
| Core Web Traffic | TCP 80, 443 and UDP 443 to Zoom web destinations | Login, updates, meeting launch, and web-based components rely on standard HTTPS connectivity. |
| Meeting Signaling | TCP 443, 8801, 8802 | Helps establish and maintain the meeting session when standard paths are constrained. |
| Meeting Media (Preferred) | UDP 3478, 3479, 8801–8810 | Audio and video quality is typically best when UDP is available for low-latency media. |
| Domain Allow List | *.zoom.us and *.zoom.com where domain filtering is enforced | Allows the client to reach the correct Zoom endpoints without being blocked by URL category rules. |
| Proxy Considerations | HTTPS proxy on 443, avoid disrupting Zoom sessions with SSL inspection | Proxy authentication prompts and interception can break secure sessions and trigger connection failures. |
If you are on a managed network, do not guess at firewall changes. Ask for a review of outbound ports, proxy behavior, and any inspection rules that apply to Zoom domains.
Device and Client Steps
After network basics, the next wins usually come from the Zoom client and the device’s connection stack. These steps are safe in most environments and help remove stale sessions and outdated components.
- Update Zoom to the latest version. In the desktop app, click your profile picture, then select Check for Updates.✅Source
- Restart the device to clear cached network state, then retry the meeting. This resets adapters and background services that can block secure traffic.
- Sign out of Zoom and sign back in. This refreshes authentication tokens and avoids edge cases tied to stale sign-in.
- Disable VPN for the test. If your organization requires a VPN, ask for a Zoom exception or a split route for meeting media.
- Check system date and time. Incorrect time can cause certificate validation failures and break HTTPS connections.
- Temporarily pause security software features that inspect encrypted web traffic, then test Zoom. If the issue disappears, create an approved exception for the Zoom client rather than leaving protection off.
If you can join from the Zoom web experience but the desktop app fails, the issue often sits in local app traffic, device security rules, or proxy handling specific to installed applications.
Use Zoom’s Built-In Network Tests
Zoom includes a Network Connectivity Tool that can test basic reachability and reveal proxy detection, routing, and meeting-service status from the client side. On Windows, open it with Ctrl + Alt + Shift + D.✅Source
What to look for in results when Error Code 104105 occurs.
- Network Information: confirms active adapter, IP, and whether a proxy is detected.
- MTR / traceroute-style views: highlights unstable hops, spikes, or routes that fail before reaching Zoom endpoints.
- Service Status checks: indicates if meetings or chat connectivity is failing from your current network path.
- Quality signals: latency, jitter, and packet loss trends that can explain join failures and media drops.
When a Network Admin Needs To Get Involved
If Error Code 104105 only appears on a corporate network, it usually requires an admin to validate policy controls. Provide the admin with a clear request focused on outbound access and inspection rules.
- Confirm outbound access for TCP 443 and meeting ports used by the Zoom client.
- Confirm outbound access for UDP media ports when real-time media is blocked by policy.
- Review whether a proxy requires interactive authentication, or modifies TLS sessions used by the Zoom desktop app.
- Check if SSL inspection or content filtering is applied to Zoom destinations and whether exceptions exist for the client.
- Validate domain filtering rules include Zoom destinations such as *.zoom.us and *.zoom.com when an allow list model is used.
A strong admin handoff includes: the exact error message, the network you were on, whether a hotspot works, and whether the Network Connectivity Tool shows proxy detection or a failed meeting-service check. This keeps the conversation anchored on evidence instead of guesses.
FAQ
Is Zoom Error Code 104105 An Account Problem?
Error Code 104105 is typically a network reachability issue, not an account restriction. If the same account works on another network or device, focus on firewall, proxy, or local security controls.
Which Settings Should I Change First?
Start with the fast checks: verify Zoom service status, test a different network, and try without VPN. These steps identify the most common root cause without changing permanent settings.
Do I Need UDP For Zoom To Work?
Zoom can operate on TCP in many cases, yet meeting quality and stability often improve when UDP is available for media. If UDP is blocked, Zoom may fall back, and some networks still produce join failures under stricter policies.
Can A Proxy Or SSL Inspection Trigger 104105?
Yes. A proxy that forces authentication, changes certificates, or intercepts TLS sessions can disrupt secure connections. If disabling the proxy path resolves the error, ask for an approved exception for Zoom traffic.
What If Zoom Works On Mobile Data But Not Wi-Fi?
That pattern points to a Wi-Fi or router constraint, or an upstream network policy. Focus on DNS, firewall rules, and any gateway controls. A restart of the router and removing VPN from the path are common fixes.
What Should I Share With Support Or IT?
Provide: your error code, the time it happened, the network type, whether a hotspot works, your Zoom app version, and results from the Network Connectivity Tool. This gives the fastest route to identifying the blocked hop or missing port access.