nadine, try this "Perform a hard reset by removing the battery from the BlackBerry smartphone and reinserting it. If the error message persists, perform a reload or upgrade the BlackBerry Device Software." from [http://btsc.webapps.blackberry.com/btsc/viewdocument.do;jsessionid=6DC3F73637462DE55FCBC4F5CD4F04B0?externalId=KB24395&sliceId=2&cmd=displayKC&docType=kc&noCount=true&ViewedDocsListHelper=com.kanisa.apps.common.BaseViewedDocsListHelperImpl|here]. The cause for the error 523 is that the phone encountered a Java Virtual Machine application related problem and is unable to continue running. Hope this helps, good luck