One thing I've found that works well with MMS is to create a Network and Connection specifically for MMS. Then you select that Network in your MMS Configuration.
Goto Start-->Settings-->Connections tab-->Connections icon-->
Goto Advanced tab-->Select Networks-->
Under Programs that automatically connect to the Internet, Click "New..." -->
Call it "Cricket_WAP", this is the Network name --> Goto Modem tab-->Click New... -->
Call it "Cricket_WAP", this is the PPP Connection name --> enter #777 --> Click Next --> Click Finish (or you can enter your user name '
[email protected]' and password 'cricket' if you do not want to be prompted for it the first time you connect) -->
Goto Proxy Settings tab --> Enable both checkboxes --> Enter wap.mycricket.com --> Click Advanced -->
Select HTTP --> change port to 8080 --> Click OK -->
Select Socks --> delete proxy name --> Click OK --> Click OK --> Click OK
Under "Programs that automatically connect to a private network, click "New..."
Call it "Cricket_MMS", this is the Network name that we will select in MMS Configuration --> Goto Modem tab-->Click New... -->
Call it "Cricket_MMS", this is the PPP Connection name --> enter #777 --> Click Next --> Click Finish (or you can enter your user name '
[email protected]' and password 'cricket' if you do not want to be prompted for it the first time you connect) -->
Click OK. We're finished setting up our connections. I recommend deleting all other Networks by selecting them on this screen, Clicking Edit, Goto General tab, clicking "Delete Settings" button.
The *only* connections you need are the two you've just created here. Any others, such as "My ISP", as just confusing and misappropriately named, and you shouldn't waste your time with them.
For example, "My ISP" is supposedly to be used to connect to the Internet, but it does not allow you to set a proxy. Instead you have to use the built-in "My Work Connection" to connect to the Internet, because it will allow you to set a proxy. When I'm setting up connections, that built-in nonsense is deleted before I even make my two cricket connections.
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Now go into MMS Configuration, and under Servers, click edit, and select "Cricket_MMS" as the network profile. Now when a new MMS is sent/received, your phone will dial up to Cricket_MMS, which has no proxy specified, and do its MMS thing, then disconnect, and reconnect to Cricket_WAP if need be. By keeping MMS seperate, you can use any browser or program you want, and it will use the global proxy setting under Cricket_WAP. Opera 8.60 is nice, but sometimes I can't or don't want to spend time to install a piece of 3rd party software in order to use my web and mms on a freshly flashed phone. True, I guess getting MMS to work requires installing the MMS cabs, but Opera should be optional, not required.
--- HAVING problems with your connection password constantly being reset to blank??? ---
The reason I started doing it this way, and at the time it seemed like more work, was that my connection settings were constantly being deleted and replaced with the default settings. Primarily it would never save my password, and I was always gettings "Invalid username/password" errors, and I would have to go into "My Connection", edit it, and sure enough my password would be blank. I'd set it, and it would work for half-day, until it was delete again. I found that no matter what I put into for connections, it would reset and always use "My Connection" with no saved password. I started by changing the name of "My Connection" to something of my choosing, just so I could see it dial "My Cricket Connection" and know it was using my settings and had not reset itself to the default "My Connection". In fact, now seeing a 6700 dial "My Connection", even if it is gonna work just fine, brings a deep-down feeling of frustration, back from the month I had this problem, and seeing it dial a unique connection name, like "Cricket_WAP", tells me it's gonna work!
If you have this problem of your connection resetting and not saving your password, the solution is to hard-reset your phone (hold down both left and right softkeys, then push reset button with stylus) and after you've calibrated your screen, you'll find yourself at a message that says, "Your device setup is complete, tap the screen to begin using Windows Mobile 5", or something. It's best at this point to position your stylus in the reset hole at the bottom of the device, then tap the screen using your finger. You'll see a message "Your device will be customized in 3 seconRAB...", as soon as you see this, QUICKLY reset by pressing the reset button with your stylus.
Do not allow *EVER* allow it to customize your device, and you'll be saved from a whole bunch of seemingly random problems. Also you'll have a completely unbranded phone, like it was meant to be from its manufactuer. If this was common knowledge, and is prominent in the stickies, I apologize for posting it again, but even today I still come accross being why know how to flash the 6700 with wap but that still don't perform this step.
Hope this helps, please let me know if any clarification would help, or maybe even if condensing this post to about the 5 or 6 items of real data it contains would be better....