When I open AAOD, I get a dialog named "Upgrade Project" stating, "Project upgrade is about to run on workspace <full qualified name>, this is a non-reversible operation. Do you want to continue?"

If I click yes, I get an error with the following exception in the error log.

Error: eclipse.buildId=4.8.0.I20180124-2000
java.version=1.8.0_251
java.vendor=Oracle Corporation
BootLoader constants: OS=win32, ARCH=x86_64, WS=win32, NL=en_GB
Command-line arguments: -os win32 -ws win32 -arch x86_64

com.avaya.sce.core
Error
Thu Mar 04 14:38:45 GMT 2021
Caught exception upgrading project. Project "<project name>" update class: com.avaya.sce.callflow.internal.CallflowProjectUpdater

java.lang.ArithmeticException: / by zero
at com.avaya.sce.callflow.internal.CallflowProjectUpdater.updateCallflow_VERSION_05_25_07(CallflowProjectUpdater.java:553)
at com.avaya.sce.callflow.internal.CallflowProjectUpdater.upgradingProject(CallflowProjectUpdater.java:179)
at com.avaya.sce.core.internal.ProjectVersionUpgradeMgr$ProjectVersionUpgradeOperation$1.visit(ProjectVersionUpgradeMgr.java:215)
at com.avaya.sce.core.internal.ProjectVersionUpgradeMgr$ProjectVersionUpgradeOperation$1.visit(ProjectVersionUpgradeMgr.java:1)
at com.avaya.ade.common.core.utils.eclipse.Extensions.loadExtensionFromPluginRegistry(Extensions.java:50)
at com.avaya.sce.core.internal.ProjectVersionUpgradeMgr$ProjectVersionUpgradeOperation.updateProject(ProjectVersionUpgradeMgr.java:232)
at com.avaya.sce.core.internal.ProjectVersionUpgradeMgr$ProjectVersionUpgradeOperation.execute(ProjectVersionUpgradeMgr.java:181)
at org.eclipse.ui.actions.WorkspaceModifyOperation.lambda$0(WorkspaceModifyOperation.java:107)
at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2214)
at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2241)
at org.eclipse.ui.actions.WorkspaceModifyOperation.run(WorkspaceModifyOperation.java:128)
at org.eclipse.jface.operation.ModalContext.runInCurrentThread(ModalContext.java:437)
at org.eclipse.jface.operation.ModalContext.run(ModalContext.java:353)
at org.eclipse.jface.dialogs.ProgressMonitorDialog.run(ProgressMonitorDialog.java:483)
at com.avaya.sce.core.internal.ProjectVersionUpgradeMgr.projectIDEUpdateCheck(ProjectVersionUpgradeMgr.java:110)
at com.avaya.sce.core.CorePlugin$1.run(CorePlugin.java:163)
at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:37)
at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:182)
at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:4218)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3825)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1150)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1039)
at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:153)
at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:681)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:595)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:148)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:152)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:388)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:243)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:656)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:592)
at org.eclipse.equinox.launcher.Main.run(Main.java:1498)


I have several questions:
Why do I need to upgrade project in the first place?
Why does the arithmetic exception occur (I don't have the code for this to look into it)?
I noticed a versioned method is called (updateCallflow_VERSION_05_25_07) is this the problem?
How do I stop seeing this error?

Thanks in advance.

Are you importing any old project? For some reason it sees you have old project version 5.x and try to do an upgrade.

I've worked this out. A process outside of AAOD on my computer had (accidentally) amended some files, causing Eclipse to not recognise the project properly. Presumably as a result of this, it was unable to verify the project version, so assumed it was out-of-date and it then tried to update it.

I closed and deleted the project from Eclipse, got a clean copy and reimported.

When I reopened Eclipse, it again prompted me to update, stating the imported project was out-of-date. This time it completed with no errors and builds seem to be working fine now.

Thanks