Black Ops 2 PS5 Can’t Join Friends? PS4 Works but PS5 Doesn’t — Here’s What to Check

Black Ops 2 PS5 Won’t Let You Join Friends?

One of the strangest problems affecting Call of Duty: Black Ops 2 on PS5 is a situation where everything looks normal — but you still cannot join your friends.

You can:

Play public matches normally

See your friends on PlayStation

Have NAT Type 2 or Moderate NAT

Host your own lobby

Receive invitations

…but when a friend invites you, nothing happens, the game freezes for a moment, or you receive an “Unable to Join Session” message.

Even stranger, some players report that the PS4 version works while the native PS5 version doesn't.

If that sounds exactly like your problem, don't immediately start changing random router settings.

There are several different problems that can produce almost the same symptom.

First: Identify Which Problem You Have

Before changing anything, perform these three tests.

Test 1 — Can you host?

Ask your friend to join your BO2 lobby.

If your friend can join you but you cannot join them, that's an important clue.

Your internet connection isn't necessarily completely broken.

Test 2 — Try the PS4 version

If you have access to the PS4 version of Black Ops 2 on your PS5, install it and repeat the same test.

If:

PS4 version → you can join friends

but:

PS5 version → you cannot join friends

you may be dealing with a PS5-version-specific issue rather than a simple PlayStation NAT problem.

Several players have reported exactly this behavior.

Test 3 — Check your NAT

On PS5:

Settings → Network → Connection Status → Test Internet Connection

Look at your NAT Type.

NAT Type 1 is Open.

NAT Type 2 is generally normal for a home router.

NAT Type 3 is restrictive.

But here's the important part:

NAT Type 2 does not automatically mean Black Ops 2 will be able to connect you to every friend's lobby.

So don't stop troubleshooting simply because your PS5 says NAT Type 2.

Fix 1: Make Sure Both Players Can Host

This is the easiest test and one of the most useful.

Have Friend A create a Multiplayer lobby.

Try joining.

Then leave and have Friend B create the lobby.

Try again.

If only one direction works

For example:

You host → friend joins successfully

Friend hosts → you cannot join

then the problem is likely related to the connection path between the two players rather than Black Ops 2 simply being offline.

Continue with the network checks below.

Fix 2: Try Joining From Inside Black Ops 2

Don't rely only on the PlayStation notification.

Try this:

Start Black Ops 2.

Enter Multiplayer.

Make sure your friend is already in a lobby.

Open the in-game Friends/Party options.

Try joining directly.

Repeat the test from Zombies if Multiplayer doesn't work.

You can also reverse the process and have your friend join you.

The goal isn't just to make the game work once.

You want to discover which direction of the connection is failing.

Fix 3: Check Party Privacy

Check the party/lobby privacy settings on both consoles.

If one player has restrictive privacy settings, joining can fail even when the PlayStation network itself is working normally.

For testing, use the most open party configuration available and make sure:

You haven't blocked each other.

Both accounts can communicate with each other.

Both players can see each other online.

Neither player is stuck in an old BO2 lobby.

Then restart BO2 and test again.

Fix 4: Restart the Entire Connection Path

Don't just restart the game.

Do a complete restart:

Close Black Ops 2.

Shut down the PS5 completely.

Turn off your router.

Wait around 60 seconds.

Turn the router back on.

Wait until the connection is completely restored.

Start the PS5.

Test BO2 again.

This won't fix a genuine PS5-version bug or CGNAT problem, but it can clear temporary session and UPnP issues.

Fix 5: Check UPnP

If your router supports UPnP, make sure it is enabled.

UPnP allows your router to automatically create the connections required by online games.

After enabling it:

Restart the router.

Restart the PS5.

Run the PS5 internet connection test.

Start BO2.

Test joining your friend again.

Don't enable multiple complicated networking solutions at once.

For example, don't immediately combine:

UPnP

DMZ

multiple port-forwarding rules

VPN

custom DNS

You want to know what actually changed.

Fix 6: Check Your Router's WAN IPv4 Address

This is one of the most important tests — especially if your PS5 says NAT Type 2 but BO2 still refuses to connect you to certain players.

Log into your router and look for:

WAN IP / Internet IP / IPv4 Address

If your router receives an address in this range:

100.64.0.0 – 100.127.255.255

you may be behind CGNAT.

CGNAT means your ISP is sharing a public IPv4 address between multiple customers.

That matters because your router may appear to have a normal internet connection while incoming gaming connections are still restricted at the ISP level.

How to Tell If CGNAT Is Your Problem

Compare the IPv4 address shown by your router with the public IPv4 address shown by an IP-checking service.

If they are different — particularly if your router has a 100.x.x.x address — CGNAT becomes a strong possibility.

For example:

Router WAN: 100.85.x.x

Public IPv4: completely different

That means the router is not receiving the public IPv4 address directly.

Why Port Forwarding May Not Fix CGNAT

This is where many BO2 guides go wrong.

You can forward ports inside your own router.

But if your ISP puts another layer of NAT before your router, your router cannot control that layer.

Think of the connection like this:

PS5 → Router → ISP CGNAT → Internet → Friend

Your router controls the first part.

Your ISP controls the CGNAT layer.

So if you're behind ISP-level CGNAT, repeatedly changing port-forwarding rules may accomplish nothing.

The Public IPv4 Test

This is one of the best ways to confirm the problem.

Contact your ISP and ask:

“Is my connection behind CGNAT? My router is receiving a 100.x.x.x WAN IPv4 address. Can you provide me with a public IPv4 address or remove CGNAT from my connection?”

Some ISPs provide a public IPv4 address automatically.

Others may require a request or an additional option.

After the ISP changes your connection:

Restart the router.

Restart the PS5.

Test NAT again.

Start Black Ops 2.

Try joining your friend.

If the connection suddenly works, you've identified the real cause.

What If Your NAT Is Moderate but BO2 Still Won't Let You Join?

This is the confusing scenario.

You have:

PS5 NAT Type 2

Your friend has:

NAT Type 2 / Moderate

Public matches work.

But:

Friend's lobby → you cannot join

Don't automatically conclude that your router is fine.

NAT Type 2 is a PlayStation classification. Black Ops 2 still has to establish the actual multiplayer session between the players.

That's why the host-direction test + PS4-version test + WAN IPv4 test is much more useful than looking at the NAT number alone.

The PS4 Version Workaround

If the following is true:

PS5 version doesn't let you join friends

PS4 version does

Your normal online connection works

Your friend can host

NAT isn't obviously restrictive

then the PS4 version can be used as a temporary workaround.

On PS5, switch to the PS4 version of Black Ops 2 and test the same lobby.

For some players experiencing the PS5-specific joining issue, this has been the only practical workaround they've reported.

The downside is obvious:

You bought/installed the native PS5 version because you want to play the PS5 version.

So using the PS4 version isn't really a permanent solution.

Important: Not Every “Unable to Join Session” Problem Is the Same

This is the biggest lesson from troubleshooting BO2 on PS5.

Two players can see the exact same message while having completely different causes.

Problem A — PS5-version-specific behavior

Typical symptoms:

PS5 version refuses invites

No useful error appears

Friends can join you

You cannot join them

PS4 version works

Problem B — NAT/network compatibility

Typical symptoms:

“Unable to join session”

Both players have restrictive/moderate NAT

Hosting direction affects the result

Other online games may have connection problems too

Problem C — CGNAT / IPv4

Typical symptoms:

Router receives a 100.64–100.127.x.x address

Public IPv4 is different

Port forwarding doesn't solve the problem

Certain players cannot connect directly

ISP-provided public IPv4 can resolve the issue

Problem D — Temporary game/service problems

Typical symptoms:

Multiple friends suddenly have the same problem

Public matchmaking also behaves strangely

Different connection setups produce the same failure

Other players report the same issue at the same time

In this situation, changing your router may not help at all.

A 5-Minute BO2 PS5 Diagnosis

Use this checklist before changing anything.

Step 1

Can you play public matches?

Yes → continue.

No → investigate the wider connection/service problem first.

Step 2

Can your friend join you?

Yes → continue.

No → test NAT/IPv4 on both sides.

Step 3

Can you join them on the PS4 version?

Yes → strong evidence that the native PS5 version is involved.

No → continue network troubleshooting.

Step 4

What is your router's WAN IPv4?

Public IPv4 → CGNAT less likely.

100.64–100.127.x.x → investigate CGNAT.

Step 5

Can your ISP provide a public IPv4?

If you're behind CGNAT and direct multiplayer connections are failing, ask the ISP.

Don't Waste Hours Changing Random Router Settings

If you've already tried:

Restarting the PS5

Restarting the router

UPnP

Port forwarding

Different hosts

PSN invites

In-game invites

Reinstalling the game

and the PS5 version still refuses to let you join friends while the PS4 version works, stop blindly changing settings.

At that point, you need to determine whether you're dealing with:

the PS5 version itself

or

your ISP/network path.

That's why the PS4-version comparison and WAN IPv4 check are so useful.

What About Port 3074?

Port 3074 is commonly associated with Call of Duty multiplayer traffic and is worth checking when troubleshooting connectivity.

However, port forwarding is not a universal BO2 PS5 fix.

If you're behind ISP-level CGNAT, forwarding port 3074 on your home router doesn't remove the ISP's NAT layer.

So test the underlying connection before creating a huge list of manual forwarding rules.

What If a Mobile Hotspot Works?

This is another powerful diagnostic.

Try connecting your PS5 through a mobile hotspot, if your mobile provider allows it.

Then test the exact same friend connection.

If BO2 suddenly works

Your home internet connection becomes the main suspect.

That could point toward:

CGNAT

IPv4 configuration

ISP routing

router configuration

double NAT

If it still doesn't work

The problem may be unrelated to your home ISP.

This doesn't prove the PS5 version is broken, but it helps eliminate your normal internet connection as the obvious cause.

The Bottom Line

If Black Ops 2 on PS5 won't let you join your friends, don't assume the NAT number tells the entire story.

Start with the simplest diagnosis:

Can you host?

Can your friend host?

Does the PS4 version work?

What IPv4 address does your router receive?

Those four questions can tell you much more than repeatedly restarting your PS5.

And if your router has a 100.64.x.x–100.127.x.x WAN address, talk to your ISP about CGNAT and ask whether they can provide a public IPv4 address.

If the PS4 version works but the native PS5 version doesn't, treat that as a separate clue rather than continuing to destroy your router settings.

FAQ

Why does Black Ops 2 say Unable to Join Session on PS5?

It can be caused by NAT compatibility, IPv4/CGNAT, router configuration, temporary service problems, or issues specific to the PS5 version. The exact symptom matters.

Why can my friend join me but I can't join them?

That can indicate that the connection works in one direction but fails when the other player hosts. Test both hosting directions and check the WAN IPv4 configuration.

Does NAT Type 2 mean my BO2 connection is fine?

No. NAT Type 2 means your PS5 is behind a router and can generally connect online, but it doesn't guarantee that every peer-to-peer gaming session will work.

Does port forwarding fix BO2 PS5?

It can help some NAT problems, but it cannot remove ISP-level CGNAT. If your router has a 100.64–100.127.x.x WAN IPv4 address, speak to your ISP.

Why does the PS4 version work but the PS5 version doesn't?

Some players have reported exactly this behavior. If your PS4 version works while the native PS5 version doesn't, use that comparison as an important diagnostic clue rather than assuming your entire internet connection is broken.

Should I use the PS4 version permanently?

It's a practical workaround if it solves your problem, but it doesn't explain or necessarily fix the underlying PS5-version issue. If you want the native PS5 version, continue diagnosing the connection and game-specific behavior.