error while importing backup to JIRA.. please help

[mohammed]

error msg:

Exception thrown during upgrade: Could not create index: SQL Exception while executing the following:
CREATE UNIQUE INDEX issue_proj_num ON jiraissue (issuenum, PROJECT)
Error was: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Duplicate entry '259-10165' for key 'issue_proj_num'
java.lang.RuntimeException: Could not create index: SQL Exception while executing the following:
CREATE UNIQUE INDEX issue_proj_num ON jiraissue (issuenum, PROJECT)
Error was: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Duplicate entry '259-10165' for key 'issue_proj_num'
	at com.atlassian.jira.upgrade.tasks.UpgradeTask_Build6132.createIndex(UpgradeTask_Build6132.java:56)
	at com.atlassian.jira.upgrade.tasks.UpgradeTask_Build6132.doUpgrade(UpgradeTask_Build6132.java:48)
	at com.atlassian.jira.upgrade.UpgradeManagerImpl.doUpgradeTaskSuccess(UpgradeManagerImpl.java:718)
	at com.atlassian.jira.upgrade.UpgradeManagerImpl.runUpgradeTasks(UpgradeManagerImpl.java:609)
	at com.atlassian.jira.upgrade.UpgradeManagerImpl.doUpgrade(UpgradeManagerImpl.java:493)
	at com.atlassian.jira.upgrade.UpgradeManagerImpl.doUpgradeIfNeeded(UpgradeManagerImpl.java:435)
	at com.atlassian.jira.upgrade.UpgradeManagerImpl.doUpgradeIfNeededAndAllowed(UpgradeManagerImpl.java:379)
	at com.atlassian.jira.upgrade.UpgradeLauncher.checkIfUpgradeNeeded(UpgradeLauncher.java:90)
	at com.atlassian.jira.upgrade.UpgradeLauncher.start(UpgradeLauncher.java:47)
	at com.atlassian.jira.startup.ActiveServicesLauncher.start(ActiveServicesLauncher.java:49)
	at com.atlassian.jira.startup.DefaultJiraLauncher.lambda$postTenantArrived$807(DefaultJiraLauncher.java:180)
	at com.atlassian.jira.startup.DefaultJiraLauncher$$Lambda$293/1236318280.run(Unknown Source)
	at com.atlassian.jira.startup.DefaultInstantUpgradeManager$StatupTask.run(DefaultInstantUpgradeManager.java:113)
	at com.atlassian.jira.startup.DefaultInstantUpgradeManager.runTask(DefaultInstantUpgradeManager.java:46)
	at com.atlassian.jira.startup.DefaultInstantUpgradeManager.doNowOrWhenInstanceBecomesActive(DefaultInstantUpgradeManager.java:35)
	at com.atlassian.jira.startup.DefaultJiraLauncher.postTenantArrived(DefaultJiraLauncher.java:173)
	at com.atlassian.jira.startup.DefaultJiraLauncher.lambda$postDBActivated$806(DefaultJiraLauncher.java:161)
	at com.atlassian.jira.startup.DefaultJiraLauncher$$Lambda$292/476926745.run(Unknown Source)
	at com.atlassian.jira.tenancy.DefaultTenantManager.doNowOrWhenTenantArrives(DefaultTenantManager.java:55)
	at com.atlassian.jira.startup.DefaultJiraLauncher.postDBActivated(DefaultJiraLauncher.java:158)
	at com.atlassian.jira.startup.DefaultJiraLauncher.lambda$postDbLaunch$805(DefaultJiraLauncher.java:147)
	at com.atlassian.jira.startup.DefaultJiraLauncher$$Lambda$43/483626030.run(Unknown Source)
	at com.atlassian.jira.config.database.DatabaseConfigurationManagerImpl.doNowOrEnqueue(DatabaseConfigurationManagerImpl.java:298)
	at com.atlassian.jira.config.database.DatabaseConfigurationManagerImpl.doNowOrWhenDatabaseActivated(DatabaseConfigurationManagerImpl.java:194)
	at com.atlassian.jira.startup.DefaultJiraLauncher.postDbLaunch(DefaultJiraLauncher.java:137)
	at com.atlassian.jira.startup.DefaultJiraLauncher.lambda$start$803(DefaultJiraLauncher.java:103)
	at com.atlassian.jira.startup.DefaultJiraLauncher$$Lambda$4/1585931757.run(Unknown Source)
	at com.atlassian.jira.util.devspeed.JiraDevSpeedTimer.run(JiraDevSpeedTimer.java:31)
	at com.atlassian.jira.startup.DefaultJiraLauncher.start(DefaultJiraLauncher.java:101)
	at com.atlassian.jira.startup.LauncherContextListener.initSlowStuff(LauncherContextListener.java:115)
	at com.atlassian.jira.startup.LauncherContextListener$$Lambda$2/473208129.run(Unknown Source)
	at java.lang.Thread.run(Thread.java:745)

[Nic Brough -Adaptavist-]

I suspect you've run into this:

https://confluence.atlassian.com/jirakb/unable-to-migrate-from-jira-5-x-to-jira-6-x-and-above-774244597.html