Get the error while trying to connect to the server

[streetracer87]

I'm getting the failed message. What can cause this issue?

[taviso]

What OS is this on? 0xc0000041 is STATUS_PORT_CONNECTION_REFUSED, it might be caused by the recent changes Microsoft made if you applied the August security patches.

I haven't had time to understand the recent changes yet, but will support it soon! I think Microsoft changed the size of the connection message, so it no longer matches.

[JoeDibley]

Can confirm this is the August Security Update

[ivanquin33]

I had the same problem "Failed to send message to server, giving up, 0xc0000024" running the ctftool.exe with non-admin account on a Windows 7 x64 VM with no updates at all.

[k4nfr3]

Confirm too. It worked before applying the security update last night, and no longer today (Win10).
Looks like a quick and dirty fix

[ibrasec]

same issue here, although no updates done to win7, but the exploit didn't sucess, instead the user just logged out untill he pass the authentication. this message keep appearing "Failed to send message to server, giving up, 0xc0000024"

[ingm4r]

Any news on this?

[ustayready]

Anyone diff the August Security Update yet to see what changed? If I get some time this weekend, I'll see what I can find.

[taviso]

I'm told there are more changes planned for next Patch Tuesday to address the edit session attacks, so I'm reluctant to do too much work on this until the new patches are released. I guess we'll see what happens!

[ustayready]

That makes sense. I appreciate the heads up, I may stand down until after Tuesday too.

[ustayready]

I went ahead and looked into the MSU, looks like the only ALPC changes I found were in CoreMessaging.dll so I diff'd pre-August vs. August. Two partial matches:

Microsoft::CoreUI::Registrar::ServerConversationOperations::RegisterConversation
Microsoft::CoreUI::Registrar::RegistrarServerCaller::LocalClientDisconnected_MessageCall

Figured I'd at least update this issue with some notes in case it becomes useful.

[Ziowebbo]

I'm told there are more changes planned for next Patch Tuesday to address the edit session attacks, so I'm reluctant to do too much work on this until the new patches are released. I guess we'll see what happens!

any update on this after many months? :)