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I try my application run on eclipse but i found these errors. which is faced first time so would you please give me any ideas for these error. i am currently using Nexus mobile.
[2011-08-04 15:59:09 - App] Android Launch!
[2011-08-04 15:59:09 - App] adb is running normally.
[2011-08-04 15:59:09 - App] Performing com.horror.android.AppActivity activity launch
[2011-08-04 15:59:09 - App] Automatic Target Mode: using device 'HT9CRP800333'
[2011-08-04 15:59:09 - App] Uploading Test.apk onto device 'HT9CRP800333'
[2011-08-04 15:59:09 - App] Failed to install Test.apk on device 'HT9CRP800333': Unable to open sync connection!
[2011-08-04 15:59:09 - App] java.io.IOException: Unable to open sync connection!
[2011-08-04 15:59:09 - App] Launch canceled!
Why i am getting java.io.IOException: Unable to open sync connection! . Thanks in Advance.
No it is not about your code. Try to plug usb out and than plag it in again. If it is not help try to reboot you device. Usually it works for me in such cases.
get into Settings->Development->, and try disabling 'USB debugging' and enabling the same
From Your Computer:
Try restarting ADB:
adb kill-server
adb start-server
For Linux(I have to do this on Ubuntu):
sudo -i (for root)
adb kill-server
adb start-server
Script I made in my '.bashrc':
alias fixadb="sudo sh -c '/path/to/adb kill-server'; sudo sh -c '/path/to/adb start-server';"
For Windows:
Ctrl + Alt + Del - Open Task Manager
Kill adb.exe
Right-click on adb.exe, Run as Administrator
USB Ports:
Try switching USB ports, this usually helps me every once in a while.
From your Phone:
Android SDK < 11:
Settings > Development > Try disabling and re-enabling 'USB debugging'
Android SDK > 11:
Settings > Developer Options > Try disabling and re-enabling 'Android debugging'
Try restarting your phone
来源：https://stackoverflow.com/questions/6939741/java-io-ioexception-unable-to-open-sync-connection-in-to-the-nexus