An error “IndexOutOfBoundsError” occured after the robot taps the element.

[testerchao]

I'm getting an error when run ruby scripts using appium with enable robot settings. I have calibrated the device and am passing the calibration script. I'm using the ruby scripts and Appium 1.4.16 and selenium-webdriver 2.50.0. The appium inspector drives the robot well. But when I run the scripts it throws the error below:

/Library/Ruby/Gems/2.0.0/gems/selenium-webdriver-2.50.0/lib/selenium/webdriver/remote/response.rb:70:in assert_ok': undefined status object (Selenium::WebDriver::Error::IndexOutOfBoundsError) from /Library/Ruby/Gems/2.0.0/gems/selenium-webdriver-2.50.0/lib/selenium/webdriver/remote/response.rb:34:ininitialize'
from /Library/Ruby/Gems/2.0.0/gems/selenium-webdriver-2.50.0/lib/selenium/webdriver/remote/http/common.rb:78:in new' from /Library/Ruby/Gems/2.0.0/gems/selenium-webdriver-2.50.0/lib/selenium/webdriver/remote/http/common.rb:78:increate_response'
from /Library/Ruby/Gems/2.0.0/gems/selenium-webdriver-2.50.0/lib/selenium/webdriver/remote/http/default.rb:90:in request' from /Library/Ruby/Gems/2.0.0/gems/selenium-webdriver-2.50.0/lib/selenium/webdriver/remote/http/common.rb:59:incall'
from /Library/Ruby/Gems/2.0.0/gems/selenium-webdriver-2.50.0/lib/selenium/webdriver/remote/bridge.rb:645:in raw_execute' from /Library/Ruby/Gems/2.0.0/gems/selenium-webdriver-2.50.0/lib/selenium/webdriver/remote/bridge.rb:623:inexecute'
from /Library/Ruby/Gems/2.0.0/gems/selenium-webdriver-2.50.0/lib/selenium/webdriver/remote/bridge.rb:385:in clickElement' from /Library/Ruby/Gems/2.0.0/gems/selenium-webdriver-2.50.0/lib/selenium/webdriver/common/element.rb:73:inclick'
from CodeMakerTest.rb:17:in `

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