As in politics, the computer world is divided. Nerds memorize data and program computers but lack intuition; intuitive types write manuals and marketing and don't program computers. Between the two crowds of brainless servants, they managed to miss out on search engine population with this error.
If you're in Windows 95, 98 or 2000/XP and you get this error:
"Cannot connect to [hostname]: 0x2747"
You'll probably figure you're just screwed if you do a Google search on 0x2747. None of those "genius" computer types figured out that this is a recurring problem and needs to be publicized. So here I am, with some fixes.
First, realize this error code has a name: WSAENOBUFS
This is the name of the Winsock error, and allows you to find the information more efficiently than when trying to use the error number (in the computer world, error numbers exist so they cannot be indexed in search engines, requiring that you hire someone instead of being able to fix the computer yourself in ten minutes, as it should be with something this simple).
WHAT IS CAUSING THIS ERROR:
Many things can. The most common are domain misconfigurations, especially with Windows 2000 and XP, but if you're running Windows 95 or an early Windows 98 and get this, it's most likely that the error is literal. You don't have enough network buffers to connect to as many hosts as you're attempting to connect to.
This means, of course, that somewhere in Windows 95/98 there is a number fot he amount of network hosts to which you can connect. Within reason, this number can be changed with a small amount of editing.
First, backup your registry.
1. Go into \windows 2. Copy system.dat and user.dat to a separate folder
Next, locate the value you need to change:
1. Go into a DOS window and type "regedit" or type "regedit" in the Run window. 2. Go to this key:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD\MSTCP\
Select it, and a list of names and values will show up in the right hand window.
Add, of type "String":
MaxConnections "255"
N.B.: You can obtain a list of opened sockets (including sockets in close state) by typing the following at a DOS prompt:
netstat -an | more
If there is no MaxConnections value set, the default is 100; if you see approximate 100 or more lines in the netstat readout, this is your problem.
Here's a good definitive link on this topic:
http://www.proxyplus.cz/faq/articles/EN/art10002.htm