Device error 400

When adding, deleting, or updating applications on your BlackBerry smartphone, your BlackBerry device resets itself and stops responding.You receive the following error message:
Device error 400

1. Disconnect your Blackberry smartphone from your computer.
2. Open BlackBerry Desktop Manager.
3. Open BlackBerry Application Loader.
4. Reset your Blackberry smartphone.
5. When the LED indicator has turned on, reconnect the BlackBerry smartphone to the computer.
6. Click Next.
7. On the following screen you will see either USB:Unknown or USB:; click Next.
8. Select the required applications from the applications list and click Next. The firmware is loaded to your BlackBerry smartphone.
   

Warning: The following procedures will delete either all data, or all data and applications on the BlackBerry smartphone. Back up the data on your BlackBerry smartphone before performing this procedure.

Please confirm that which installation software you want for your Blackberry 7290.
Is it Norton Antivirus,
Desktop Manager,
Device Software.
And let us know to provide the proper instructions.

An unspecified error has occurred with an application on your Blackberry smartphone.


Resolution In BlackBerry Desktop Manager, run the BlackBerry Application Loader tool.
Note: The following procedure will delete all data and applications from your BlackBerry smartphone.

1. Disconnect your Blackberry smartphone from your computer.
2. Open BlackBerry Desktop Manager.
3. Open BlackBerry Application Loader.
4. Reset your Blackberry smartphone.
5. 1. Remove the battery cover.
   2. Remove and reinsert the BlackBerry battery to reset the BlackBerry smartphone.
   3. Replace the battery cover.
   To perform a hard reset on a RIM 850 device, RIM 857 device, RIM 950 device, or RIM 957 device, insert the end of a paperclip inside the small hole on the back of the BlackBerry device.
   
6. When the LED indicator has turned on, reconnect the BlackBerry smartphone to the computer.
7. Click Next.
8. On the following screen you will see either USB:Unknown or USB:; click Next.
9. Select the required applications from the applications list and click Next. The firmware is loaded to your BlackBerry smartphone.
   

Warning: The following procedures will delete either all data, or all data and applications on the BlackBerry smartphone. Back up the data on your BlackBerry smartphone before performing this procedure.

I do apologize you are having this issue with the Blackberry pearl 8100. Lovely device.
The manufactur, RIM is aware of the memory issue. It's a known malfunction of the device. Luckily, there's a way to fix it, and keep your pictures, logs, address book, etc.. from deleting.
First, you should have a 1GB card for your photos.
Second your phone stores what it does. So, when ever you exit an application press the back button. NOT the hang up button. It'll only leave that application running in the back ground.
Third, you can clear history by holding on ALT+LG+LG. You'll get an event log. Press MENU key, and select "Clear history".
Next, clear the cashe. Open up Internet browser, press the menu key and select clear cashe. Once you have done that, press the back button to the begining. Save all pictures on the memory card. If you don't have memory card, connect your Blackberry to your PC and use the desk top manager to sync your media over via USB cord.
Now, that you are connected via USB cord and have the desk top manager up, run application loader. This should take a total of 20 minutes. Do not REMOVE from the cord. You'll ruin the OS on the Pearl.
Once all is cleared out, and updated. Do a check on your camera, your call log, and sms's. Periodically, delete your text messages. I would say, once or twice a month run the application loader. You can always check out www.t-mobile.com/bbupgrade for the latest and great software for you Blackberry. Or, go to www.blackberry.com/btsc for tips & tricks!
RIM always updates their software every 2-4 months. That way you'll keep your Blackberry longer and stronger! Enjoy!

Cheers!

You may need to clear out the calendar database first on the BlackBerry device, and then try to synch again. Do the following:

1. Connect your BlackBerry via USB.
2. Open Desktop Manager and go to the Backup and Restore option.
3. Select Advanced.
4. The Desktop Manager will show the device databases on the right-hand side.
5. Scroll down and highlight the entry that says Calendar, then click on the Clear button.

Once Desktop Manager has cleared the calendar database try to sync again.

There is a few details we need in order to help you better solve your problem. Please let me know the following:

1. What action on your Blackberry are you trying to do that gives you the ERROR 400 message?
2. Are you trying to browse the internet whent his action happens or just any programs?
3. Are you trying to use your phone under a shared work system?
4. Are you on an individual plan or company plan?
5. Are you able to do anything after that error message shows up?
6. If you turn off your phone, take out the battery for a full minute, then put it back in, does that solve this error message?
7. Is this a new error message or has this happened to you before?

Let me know the answers to these questions in order to better assist you with a solution. We're looking forward to your response!

Could someone help me with Device Error 400 for Blackberry 7290 please? I have this error since yesterday and can't resove it. If anyone can help me with would me great.

Thanks.

hxxp://blackberryforums.pinstack.com/10781-jvm_error_102_step_step_fix.html
Read this thread carefully

All you have to do is use the desktop manager (DM) you should have loaded when you got the phone. if you didnt load the software, go on www.blackberry.com/software to get your version of desktop software. plug the data cable into the phone and do a "hard sync". from the DM, pick the application loader, add load your phone's new version of software. If your pc doesn't see the BB (which is inevitable because pc/windows is trash) restart both pc and the bb. Again, plug the cable into the BB first then into the pc. Once this is complete any info you had on the phone is gone. Sorry, should have used the desktop software before you had a problem :P
NOTE: YESS, mac users there is a desktop manager software for us finally! I believe you have to have "leopard" 10.5.4 or higher. :D

try searching the contact list with letter 'a' then click on the first contact then select 'delete lookup' then repeat this all through the alphabet and it should clear the contacts list.