Slack performance and loading issues can disrupt workflow, but most problems can be resolved through systematic troubleshooting. The most common causes include connectivity failures, outdated apps, hardware acceleration conflicts, and network restrictions. Start by checking Slack's system status to rule out service-wide outages, then focus on local solutions like clearing cache, disabling hardware acceleration, or adjusting network settings. For persistent issues, collecting diagnostic logs and contacting Slack support is recommended.

Key findings from the sources:

• Hardware acceleration is a frequent culprit for slow performance on Windows and macOS ^[4][7]
• Network restrictions (firewalls, proxies, antivirus) often block WebSocket connections required by Slack ^[2]
• Cache clearing and app restarts resolve 60%+ of loading issues ^[1][5]
• Slack's built-in connection test (accessible via Help > Troubleshooting) identifies WebSocket problems ^[2][10]

Troubleshooting Slack Performance Issues

Desktop App Optimization

Slack's desktop app performance issues often stem from hardware acceleration conflicts or corrupted cache. On Windows, users report immediate improvements after disabling hardware acceleration through the app's advanced settings ^[4][7]. This feature, while designed to improve rendering, can cause slowdowns on both high-end and standard machines. The process involves navigating to Preferences > Advanced > Other options and checking the "Disable hardware acceleration" box before restarting Slack.

For macOS users, similar steps apply, though the path may vary slightly depending on the version. Additional desktop-specific solutions include:

• Clearing app cache: Accessible via Help > Troubleshooting > Clear Cache and Restart ^[1]
• Reinstalling the app: Uninstall completely, download the latest version from slack.com/downloads, and install fresh ^[5]
• Updating the app: Outdated versions often have unresolved bugs; check for updates via Help > Check for Updates ^[2]
• Running connection tests: Use Slack's built-in tool (Help > Troubleshooting > Connection Test) to verify WebSocket connectivity ^[2]

Hardware acceleration issues manifest as sluggish scrolling, delayed message loading, or frozen UI elements. Users with NVIDIA graphics cards report higher incidence rates, suggesting driver conflicts ^[4]. If disabling hardware acceleration doesn't resolve the issue, the next step is collecting Net Logs for Slack support, accessible through the same Troubleshooting menu.

Network and Connectivity Solutions

Slack requires persistent WebSocket connections over port 443, which corporate networks often restrict. The most common network-related symptoms include "connection failed" errors, infinite loading spinners, or sudden disconnections ^[2]. Workspace admins should verify that their firewalls allowlist Slack's required domains, including:

• *.slack.com
• *.slack-core.com
• *.slack-edge.com
• *.slack-files.com ^[2]

For individual users experiencing connectivity issues, the following steps resolve most cases:

• Temporarily disable antivirus/firewall: Programs like Norton, McAfee, or Windows Defender may block Slack's WebSocket traffic ^[2]
• Test alternative networks: Connect to a mobile hotspot to determine if the issue is ISP-specific ^[10]
• Check proxy settings: Misconfigured proxies can interrupt Slack's persistent connections; verify with IT if on a corporate network ^[2]
• Run Slack's connection test: Available at https://slack.com/help/test to diagnose WebSocket failures ^[2][10]

Network administrators should also monitor for bandwidth saturation during peak hours, as Slack's real-time syncing consumes significant resources. PingPlotter Professional can map connection paths to identify latency spikes between the user and Slack's servers ^[10]. If issues persist after these steps, Slack's support team requires Net Logs (collected via Help > Troubleshooting > Restart and Collect Net Logs) for deeper analysis.

For browser users, additional steps include:

• Disabling browser extensions: Ad-blockers like uBlock Origin or Privacy Badger may interfere ^[1]
• Switching browsers: Chrome and Edge typically perform better than Firefox for Slack web ^[5]
• Clearing browser cache: Particularly for "loading trouble" errors with error code 100054 ^[1]