hmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm minecraft

AVG Antivirus

All Versions

Causes download problems.
Uninstall Tool here

BitDefender

All Versions

Causes download problems, login issues and problems connecting to LAN worlds.
Uninstall instructions here

ByteFence

All Versions

Causes download problems, reputation questionable.
Uninstall instructions here

Comcast Constant Guard

All Versions

Causes control issues.
Uninstall Tool here

Comodo Internet Security

All Versions

Causes login and multiplayer connectivity problems.
Disabling the firewall will help, but it is recommended that you uninstall it.
Uninstall Tool here

ESET Antivirus

All Versions

Causes login and multiplayer connectivity problems.
ESET Security has a feature that interferes with Minecraft’s ability to connect to Mojang’s servers. To fix it, follow these instructions here, and set the mode to Interactive. Then, open the launcher and try to log into Minecraft. ESET will open a window asking what to do, press EXCLUDE.
If the above fix does not work, you will need to uninstall ESET Antivirus.
Uninstall Tool: Windows / Mac

Kaspersky Internet Security

All Versions

Causes login and multiplayer connectivity problems.
If you are using Kaspersky Internet Security and cannot connect to Mojang’s servers, turn off Encrypted Connections Scan by following this guide.
If the above fix does not work, you will need to uninstall Kaspersky Internet Security.
Uninstall Tool here

Lavasoft Ad-aware Web Companion

All Versions

Causes login and multiplayer connectivity problems.
After you have uninstalled it from the Control Panel, follow these instructions here to complete uninstalling Ad-aware.

McAfee Anti-virus / Intel Security

All Versions

Causes login and multiplayer connectivity problems.
Uninstall with MCPR Tool found here

Norton Antivirus

All Versions

Causes download, login and multiplayer connectivity problems, degrades performance.
Uninstall Tool here

PCKeeper / MacKeeper

All Versions

Causes login and multiplayer connectivity problems, degrades performance, reputation questionable.
Uninstall instructions: PC / Mac

Reason Security

All Versions

Causes download errors, as well as login and multiplayer connectivity problems, degrades performance.
Uninstall instructions here

Webroot SecureAnywhere

All Versions

Causes login and multiplayer connectivity problems.
If you’re having issues joining a LAN world while using Webroot SecureAnywhere, open your settings, navigate to System Tools –> System Control –> Control Active Processes and make sure Java and Minecraft are set to Allow.
Uninstall instructions if uninstall fails

ZoneAlarm Firewall

All Versions

Causes login and multiplayer connectivity problems, degrades performance.
Uninstall Tool here

Covenant Eyes

Versions below 7.2.41

Causes login problems.
The latest version fixes the problem with Minecraft. To install the latest version, log into your Covenant Eyes account here, go to the Downloads section, and download version 7.2.41 or newer. If you have a much older version of Covenant Eyes (4.5.3 or older), uninstall Covenant Eyes and then install it again with the most recent version.
If the above fix does not work, you will need to uninstall Covenant Eyes.
Uninstall instructions here

Qustodio

Some old versions

Causes download and login problems.
The latest version fixes the problem with Minecraft. To install the latest version, uninstall Qustodio, restart your computer, and reinstall it from Qustodio’s website. After this restart your computer again.
If the above fix does not work, you will need to uninstall Qustodio.
Uninstall instructions: Windows / Mac

PremierOpinion

All Versions

Causes general and memory related crashes. Commonly crashes the game with exit code -805306369.
Download AdwCleaner, run a Scan, then Quarantine. Restart when AdwCleaner has finished cleaning, then try running the game again.

RelevantKnowledge

All Versions

Causes crashes and game performance issues.
Download AdwCleaner, run a Scan, then Quarantine. Restart when AdwCleaner has finished cleaning, then try running the game again.

WebCompanion

All Versions

Causes crashes and game performance issues.
Download AdwCleaner, run a Scan, then Quarantine. Restart when AdwCleaner has finished cleaning, then try running the game again.

IDMan

All Versions

Not Detected by ADWCleaner Presents like a VPN, Can cause download issues and other issues with the game
Download Malwarebytes run a Scan, then Quarentine. Restart when Malwarebytes tells you to, then try running the game again.

D3DGear

Versions below 4.50.1846

Crashes Minecraft.
Later versions of D3DGear have fixed this problem. To fix this problem, uninstall D3DGear and install the latest version.

Discord

All Versions

Causes freezes or crashes.
Disable the Overlay feature in Discord.

Evolve and/or Player.me

All Versions

Causes freezes or crashes.
Disable the the Ingame Overlay feature.

GeForce Experience

All Versions

Can cause crashes, freezes and mouse control issues.
Disabling the in-game overlay should solve this issue. Laptop users should also disable Whisper Mode and Battery Boost.

Razer Synapse / Razer Cortex

All Versions

Crashes the game with exit code -805306369 or Out Of Memory Errors by limiting the amount of memory Minecraft is allowed to use.
Uninstall the software then delete _JAVA_OPTIONS=-Xmx256mb (or 512mb) from your Enviroment Variables.

Symless Synergy

All Versions

Breaks mouse movements in Minecraft.

Hamachi / Tunngle

All Versions

Causes login and multiplayer connectivity problems.
Fundamentally conflicts with the Internet as it is squatting on an occupied block of IPv4 address. Also has the tendency to break Minecraft multiplayer.
For proper server hosting, set up port forwarding on your router or use a server hosting solution (such as Minecraft Realms).

Hola Unblocker

All Versions

Causes login problems.
Turns your computer into a botnet, allowing malicious users to use your internet connection for illegal activities; see this website for more details.

All free VPNs and some paid VPNs

N/A

Causes login problems.
Mojang has blocked most VPN users from logging into Minecraft as these free VPNs are often used by malicious users to hack into accounts.