Going to disagree.

Pick 10 allows many more customizable things that previous/games w/o pick 10 just don't allow you to do.

Want three attachments on a gun? Pick 10.
Want 6 perks without kills? Pick 10.

Just a couple examples.

In this guide, I'll be showing you how to repair your IW5 Installation.

Requirements:

Steam

Instructions:

Open Steam and check Tools under the Games dropdown, by the search bar.

Search for Call of Duty Modern Warfare 3

Right-click the Call of Duty Modern Warfare 3 - Dedicated Server, then click Properties

Now click on the Local Files tab, followed by Verify Integrity of game files

Congratulations, your game files should now be repaired.

// Locked at request of OP.

Server guide for T4

Requirements:
A PC/VPS, running either Windows 10 or Windows Server 2019.
The ability to port forward
A Plutonium forum account
Notepad++/Any other code editor

In this tutorial, I will assume that you have installed T4 to C:\T4 already.

1. Preparation

1. Download the Plutonium Launcher
2. Download the Updater.bat [Do a CTRL+S on the page that opens]
3. Download the Start.bat
4. Download the Server.cfg file and move it to the main folder.
   
5. Save/Move all files to C:\T4

1.2 Creating a server key
0. Set the server name you want in your server.cfg file.

1. Open the Plutonium Server Key page.
2. Fill in the name of the server and select the correct game.
3. Click on create, then copy the server key.
4. Paste the key into the Start.bat file under set key=xxxx, replace xxxx with your key.

2. Basic configuration and the first start
Edit your Server.cfg file with whatever changes you want (i.e. RCON Password/Map Rotation/Round Limits/etc/etc).

Launching the Server:
Double click the bat file.
Wait for the server to finish loading.

4. (Optional) Install a server management tool

5. (Optional) Hosting a second server
Make a copy of the Start.bat file and the Server.cfg file and rename them.
Edit the Server.cfg to have a new hostname, and grab a key for it.
Edit the copy of the bat file to have a different port/your new key and to use your second cfg.
(You must forward the second port as well)
Start the server through the new .bat file.

FAQ
Q: Why can't I find my server hosted at home while others can?
A: Your router probably doesn't support NAT-Loopback (aka. NAT-Reflection) and that's why it doesn't know how to forward the network traffic. In order to connect it use your internal IP or 127.0.0.1 if its hosted on the same machine.

If you open the game console with the tilde key, you can type

/unlockall

and you will get everything.

You were banned by IW4MAdmin's server-side anticheat, sometimes it slips up. Create a ticket in #ban-appeals and I can help you out. That discord link is correct that Dss0 put.

Edit: I've just lifted your ban, since I'm sure the server side anticheat had a hiccup.

go read this
https://forum.plutonium.pw/topic/2819/how-to-install-update-plutonium-t6

I had this exact same issue, make sure all servers are closed and your updater matches mine (I was missing the ./)

plutonium.exe -install-dir ./ -update-only

You were banned by our server side anticheat. No human banned you. Learn how to read before bitching about this and attacking the project. [Learn how to appeal by reading Leon's message]

Update to Windows 10.

@Kajuiz Your key is in the wrong place. You are meant to place it in the set key= on line 3, not in the variable in line 21.

You need to install everything inside the redist folder in your game location.

Alternatively, give the redist installer a shot.

I also saw it in the server list, forgot to mention.

I was able to /connect 85.146.167.143:27017 to it just fine.

I have an RX 460 & can hit 333 on 1080p, so check your drivers and such. Something might be off.

Nothing we can do for current bans.
Please reference our anticheat policy.

In the future, if you are to use mod menus use LAN Mode in the launcher.

Would be helpful if you included a screenshot. Saying it doesn't work isn't helpful.

unlockall or if you want diamond camo along with max level, follow this guide

You do not appear to be banned from that specific server.