Can not switch to phone function

You can use the Unlock code to Unlock Your Palm-One Tero 650 model Phone,You can get the Unlock code from here
Wickedunlock and follow the instructions and Unlock it step by step..
Palm One Treo 650 Unlocking InstructionsWarning : Do not enter any wrong unlock codes on your Palm One Treo 650 mobile phones. If you enter over a certain amount of wrong unlock codes on your Palm One Treo 650 mobile phone, your phone may get hard locked and sometimes become unusable.
1 - Switch ON your Palm One Treo 650 with an ACCEPTED SIM Card,
2 - Go to Menu and select "Phone Tool" or "Phone Application",
3 - Type on Virtual Keyboard *#*#CODE#,
4 - Select with PEN "Numer" and Palm One Treo 650 will show that it's unlocked now!

or

1 - Switch ON your Palm One Treo 650 with a NOT ACCEPTED SIM Card,
2 - Enter the Unlock Code we send to you.

or

1. Remove Palm One Treo 650 battery, unplug cable,
2. Switch ON your Palm One Treo 650 with a NOT ACCEPTED SIM Card,
3. 'Sim not allowed' is displayed, click OK,
4. Go to the dial pad, and dial *#*#CODE#,

CODE: The unique unlock code for your Palm One Treo 650.
ACCEPTED : We mean, to use a sim card from the network your Palm One Treo 650 is locked to.
NOT ACCEPTED : We mean, to use a sim card from a network other than the network your Palm One Treo 650 is locked to.

Normal 0 Hi,
The best thing I can do for you is to refer you to the free palm chat. For the palm phones I have to know what service provider you use to be able to get you to the correct link. So here is a link to palm support for your phone. Click on the icon for your service provider (Rodgers, AT & T or Palm) From there you want to click on the words “support services” at the top of the page. If you have selected AT&T on the previous page you will be able to do a palm chat. The link for the free chat is located in about the middle of the page. If you have any other provider besides AT&T you have the option to start a repair ticket or if it is under warranty there is a number to call. Best wishes…I hope this will help you.

http://kb.palm.com/wps/portal/kb/na/deviceselector/page_en.html#NA%20Phones:Treo%20750

hi there,
call the customer service of your service provider ( AT&T,Vodafone,Verizon etc)....they will set up message center number on your phone , the one that you have might be incorrect...your mobile operator will send you sim updates that will refresh the settings ....and then you will get the text message options
cheers

I have the same problem using an unlocked Treo 650 on O2(UK).
One thing you need to do is make sure that the Message Centre Number is set correctly for the SIM network you are using. Get the MCN from the internet, then on the Treo Messaging > Menu > Options > Preferences > Network > Manual > Edit to check/set the MCN.

LOL....that is the crappy thing about this phone. Can't receive text pictures either...have you noticed that? I LOVE everything else about this phone.

I don't understand how you can surf the net, download webpages and pictures, but you can't recieve a text picture or send a picture to anyone! baffles me....but I still love this phone.

contact cricket and get there messae centre number of them, enter this into the option on your message settings, also get them to send you a sim update and also a gprs message update this will sort all your problems

I also have a Treo 650 that works flawlessly. I'm on AT&T and sometimes a message gets delayed but I don't think I've ever missed a message. I would believe it is the verizon network. It could also be effected by sunspots and the part of the world you are in.

good luck

Hello, hope it helps (from http://www.chaddickerson.com/blog/2006/05/19/what-to-do-when-sending-an-sms-makes-your-treo-650-reboot/)

The application that causes the reboot varies, but it’s always the same error related to the message store. Here’s how you fix it (and beware — this deletes all the text messages on your device!):

1. If you don’t already have it, you need to download and install FileZ on your Treo. All this does is give you access to all the files on the Palm OS filesystem. This is a tool that must be used very carefully, since you can move, copy, and delete any files on the Treo, even ones you didn’t know were there. It’s one of the most useful Treo utilities you can have.
2. Run FileZ on your phone and choose “View and Edit Files.” In the next screen, you should see “Internal” under Filename. It might also say “ROM.” If you have an SD Card, you should also see “External” or “SD Card.”
3. Click on the little wedge beside “Internal” to expand the list of files on your Treo.
4. Find Messages Database and delete it (you do this by checking it, choosing “Details,” and then clicking “Delete”)

have you try this? :

Hi

Have you gone under Preferences -> and disabling the auto keygaurd

there are 2 options

incoming calls received +

on a call

try disabling both these options and let me know what happens