10 Most Common Minecraft Server Issues (and How to Fix Them)

Running a Minecraft server is awesome, until something breaks. Whether you’re hosting for friends or managing a community hub, you’ll eventually face issues like lag spikes, mod conflicts, or players unable to connect.

The good news? Most problems have simple fixes once you know what to look for.

In this guide, we’ll walk through the 10 most common Minecraft server issues and show you exactly how to troubleshoot them.

1. Lag and Performance Drops

Problem

Players experience choppy movement, slow block-breaking, or delayed chat and combat, your server feels like it’s running underwater.

Common Causes

• Too many entities (mobs, dropped items, redstone machines).
• Low TPS (ticks per second) due to inefficient plugins or world size.
• Insufficient RAM or weak CPU.
• Outdated or unoptimized server type (e.g., Vanilla vs PaperMC)

Potential Fixes

✅ Switch to PaperMC or Purpur for better optimization.
✅ Limit mob farms and redstone tick rates.
✅ Upgrade your hosting plan or allocate more RAM.
✅ Use Spark to analyze lag spikes and plugin impact.
✅ Use entity limits.
✅ Tune Paper config
✅ Pre-generate your world with Chunky

2. “Can’t connect to server”

Problem

Players see messages like “Connection refused”, “Timed out”, or “Failed to connect to the server.”

Common Causes

• Server is offline or crashed.
• Wrong IP address or port.
• Firewall blocking inbound connections.
• Player using a different Minecraft version.
• Port forwarding not configured for self-hosted setups.

Potential Fixes

✅ Double-check your server IP and port (default 25565).
✅ Ensure the server is running and online.
✅ Update both server and client to the same Minecraft version.
✅ Configure port forwarding in your router.
✅ If using a host, verify your subdomain or DNS is correctly linked.

3. Outdated Server

Problem

Players can’t join, plugins crash, or the console shows version mismatch errors after a new Minecraft update.

Common Causes

• Server still running an older Minecraft version.
• Plugins or mods not updated for latest release.
• Outdated Java runtime version (e.g., running Java 8 on Minecraft 1.20+).

Potential Fixes

✅ Always use the same version as your players.
✅ Update plugins and mods from trusted sources (SpigotMC, CurseForge).
✅ Use ViaVersion. It lets newer clients join older servers.
✅ Use Java 21 for 1.20.5+

4. “Internal Server Error” or “Read Timeout”

Problem

Players are suddenly disconnected or can’t join, often seeing “Internal Server Error” or “Read Timeout.”

Common Causes

• Corrupted player data files.
• Broken plugin or mod.
• Incompatible server software.
• Overloaded CPU

Potential Fixes

✅ Check your latest.log for errors when a player joins.
✅ Delete that player’s .dat file in /world/playerdata/.
✅ Remove recently added plugins/mods.
✅ Test your setup on Paper or Spigot for better error tracking.

5. World Corruption

Problem

Your world loads incorrectly: missing chunks, players spawn in the void, or the server crashes when loading an area.

Common Causes

• Server forced closed instead of stopping properly.
• Insufficient disk space during a save.
• Hardware crash or incomplete world backup.
• Mod or plugin-generated terrain errors.

Potential Fixes

✅ Use Region Fixer to repair corrupted chunks.
✅ Restore your most recent backup.
✅ Always use the /stop command before closing the server.
✅ Enable auto-backups at regular intervals.

6. Permissions and Command Errors

Problem

Players can’t use commands or access ranks; console shows “You do not have permission.”

Common Causes

• Misconfigured permissions plugin.
• Wrong syntax in LuckPerms Web Editor.
• Conflicting permission groups.
• Reloaded server instead of fully restarting.

Potential Fixes

✅ Use LuckPerms: it’s reliable and actively maintained.
✅ Open /lp editor for a visual web-based editor.
✅ Restart the server after big permission edits.
✅ Never use /reload on Spigot/Paper. Restart instead (causes broken states).

7. Ping Issues

Problem

Players experience high ping or lag spikes despite good hardware.

Common Causes

• Server located far from players.
• Poor internet routing or DDoS attacks.
• Oversaturated shared hosting node.
• Background downloads or network congestion.

Potential Fixes

✅ Choose a server region close to your main players.
✅ Enable DDoS protection.
✅ Check internet speed and router quality.
✅ Use wired Ethernet instead of Wi-Fi.

8. Plugin or Mod Conflicts

Problem

After installing new mods or plugins, the server crashes or won’t start.

Common Causes

• Running incompatible mod types (Forge vs Fabric).
• Outdated or duplicate plugins.
• Missing dependencies like Vault or PlaceholderAPI.
• Mods conflicting over the same feature.

Potential Fixes

✅ Verify compatibility between mods and your server type.
✅ Update all plugins to match your Minecraft version.
✅ Remove one mod/plugin at a time to isolate the issue.
✅ Keep a testing server for new installations.

9. Online vs Offline Mode Conflicts

Problem

Players see “Invalid session” or “Failed to verify username” errors when joining.

Common Causes

• Server in offline mode while clients use official accounts.
• Authentication issues with Mojang servers.
• Proxy setups (BungeeCord/Velocity) misconfigured.

Potential Fixes

✅ Keep online-mode=true for normal setups.
✅ Restart both proxy and backend servers.

10. Server Crashes

Problem

The server suddenly stops responding or closes mid-game.

Common Causes

• Out-of-memory errors.
• Plugin/mod incompatibility.
• Corrupted world data.
• Java version mismatch.

Potential Fixes

✅ Check the console logs for crash reasons.
✅ Allocate more RAM (especially for modpacks).
✅ Remove recently added mods/plugins.
✅ Update to the latest Java 17+ runtime.
✅ Keep backups before making major changes.

WiseHosting – The Best Minecraft Server Hosting with 24/7 Support Team

If you’d rather spend time building worlds instead of debugging them, WiseHosting is the perfect fit.

WiseHosting is the world’s highest-rated Minecraft server hosting and one of the few that exclusively focuses on Minecraft hosting only. Started by YouTuber Shulkercraft (2.4m subscribers), WiseHosting has quickly become a go-to way to host a Minecraft server.

Deep Minecraft Expertise (24/7 Support)

WiseHosting is known for their deep expertise with Minecraft servers. Their support team is ran by server admins and active system administrators who know ins and outs of running a modded Minecraft server.

You get 24/7 support from real hosting experts who understand Minecraft. Whether you have issues with installing a modpack or fixing performance issues, you are one message away from incredibly fast support.

✅ Performance Built For Minecraft

• Modern Ryzen CPUs: Smoother ticks and chunk generation.
• Paper pre-installed: Better performance out of the box (you can still switch).
• NVMe SSD storage: Every server runs on ultra-fast NVMe drives, meaning instant chunk loading and smoother saves.
• Global locations: Servers across North America, Europe, and Asia, giving players the lowest possible ping.

“I’ve never had customer support this good. It’s clear how they went out of their way to teach me how to mod a Minecraft server.” — Jorge

Final Takeaway

Every server admin, from small private worlds to huge networks, faces these 10 issues eventually.

But with proper setup, version control, and proactive maintenance, you can prevent most of them before they strike.