For the past two months, randomly when I try logging in on a toon I get DC'd back to the log in screen just as the load screen fills. Apparently I show up in game but my screen never gets that far. Once that happens Im usually locked out of my other main. If I'm lucky, logging into an alt helps. I'm running Windows XP...any ideas what's causing this or how to fix it?

I have been having this problem for 8 weeks now, and i'm sure you're aware that you have to pay monthly for the game so i'm very pissed off.
I've came here as a last resort as Blizzard tech support are unbelievabley crap.

The problem i've been having is that on 1 server, (Stormrage Server where my main characters are) I log in to the server and then i get disconnected after about 30 seconds, well not disconnected... i seem to be hanging i the game cause i can run around and the game still detects where i moved but nothing in the game i can interact with works... people run on the spot and NPC's stop and don't do anything. Then if i'm lucky i get disconnected from server and taken back to the login screen. Or usually, it just stays in this lag for around 3-4 mins, and i'm impatient so i have to Alt+F4 out of the game and load again.

The things i've tried:
Fowarded all the neccisary ports on router
Reinstalled World of Warcraft 3 times
Used the repair tool
Disabled Firewall
Created Firewall rule to allow Blizzard
Tried logging in on another computer in the house (didn't work)
My friend tried logging on on their account on my PC
Got a new Router
Connected to the router via ethernet cable
Connected to someone elses wireless connection (neighbour)
Added server IP's and logon IP's to the hosts file
Delete Interface, WDB and *** folders in World of Warcraft Folder

seems like quite a heavy lag there, ur browsing fine as normal?

What are your system specs?
What kind of local connection are you using?
Which ISP are you using? Which plan?
Anybody in your local network using p2p?

open up ur launcher see the status, because most of the time 'Applying non-crit updates..' cause me lag also. just wait til it finish..

its all done. nothing is downloading or applying updates.

before i click PLAY, it is up to date status.

Could be routing issues.
One or more of the hops to your server destination has high packet losses probably 

Call stremyx and complaint, ask them to reset port or change port

this happen to me also.
when u dc, dont login back, close the window, then run it again..
i do it 2-3 times then no problem anymore..
i use streamyx too. :/

It sounds like you're disconnecting during the initial data load when the caches are being refreshed, which happens the first time you log in.

If your broadband latency is fine, you probably need to ensure you have more swap space on your hard disk - i.e. check that the drive WoW is on isn't at a critically low space available.

FYI i had even removed folders of Cache, WTF and Interface, yet doesnt work perfectly as what im expected.

Removing the contents of the Cache, WTF and WDB only makes it worse since the game has to repopulate the item and creature cache again, so I wouldn't do it very often.

Just try running with and without addons and see whether it makes a difference.

no addons or anything 3rd party stuff, just pure installation data.

i even had repaired the application by using repair tool as well.

without any tunnel service too.

all i did and had is pure updated WoW data, normal internet connection with decent rig.

system wise: try disable sunshaft(graphic) and force to set graphic rendering mode to directx11. also set max cache size for graphic rendering(depends what gpu u using, but if you unsure PLS DO NOT touch this section, leave application determine itself))
network wise: try adjust your network mtu on both router/modem and lan card, get the best fragment size for your network. also enable large system cache and set it to balance mode(this might cause damge to your hardware in long term)

alternatively, try download tcp optimser and use it to optimise your lan card + registry setting. **USE AT OWN RISK**

there is still some tweaks around.. try these few first...

It is probably your firewall or modem. I don't know which but ever since I bought the TP-Link modem I have this constant disconnection as well whenever I reboot wow (i.e. clicking from wow launcher). It was really odd because the same damn IP which were giving me yellow latency a few minutes ago would disconnect me every time until I refresh the IP.

This may explain things.  In particular note Blizzard's quote for broadband definition,

http://us.battle.net/wow/en/forum/topic/2065776684

same problem.

normally what i do now is that i on wow then leave it there on the sign in screen for like 10mins. then log in play with no more dc and no more lag.

if lag then log out and keep wow on login screen then reset modem. then log in, problem solve

had the same problem. solved it with tunneling >,<"

try our services . hehe

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even with tunnel i do believe it doesnt fix, as i dont suffer bad lags.
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