XML removing lines between two tags

Need ur help. I used to work with reprocessing failed XML a lot in MQ. Sometimes due to some issue lots of message used to move to error queue. Here i need to reprocess the message after resolving the issue. In error queue will have data,but will error tags. message in error queue is not a proper xml. for example condiser a messgae like below

    `   <?xml version="1.0" encoding="UTF-8"?>
    <Student 
    +++++++++++++++++++++some content++++++++++++++++++++++++++++++++++++++++++
    +++++++++++++++++++++some content++++++++++++++++++++++++++++++++++++++++++
    +++++++++++++++++++++some content++++++++++++++++++++++++++++++++++++++++++
    +++++++++++++++++++++some content++++++++++++++++++++++++++++++++++++++++++
    +++++++++++++++++++++some content++++++++++++++++++++++++++++++++++++++++++
    </Student>`
    error queue message will have above message plus below error details

    <ErrorMessage>
    ++++++++++++++++++++++reason for failure will be updated below these tag with will 
    many lines    
    </ErrorMessage>


     I can download the whole message in a error queue to next format. i want to remove    the data between     <ErrorMessage> and </ErrorMessage> tags. need help for this. will it be easy to do it  with the help of textpad or notepad++

i dont have much idea abour regex experssion in notepad++. please help me on this