diff --git a/src/vs/workbench/parts/debug/common/debugModel.ts b/src/vs/workbench/parts/debug/common/debugModel.ts
index 3d2fe5c1b7eac278e8f754630b1b25317d1fbdf2..f6e408239f337c4bf5f243a812c24c43b6975bb7 100644
--- a/src/vs/workbench/parts/debug/common/debugModel.ts
+++ b/src/vs/workbench/parts/debug/common/debugModel.ts
@@ -759,7 +759,8 @@ export class DebugModel implements IDebugModel {
 
 	public addSession(session: IDebugSession): void {
 		// Make sure to remove all inactive sessions once a new session is started
-		this.sessions = this.sessions.filter(s => s.state !== State.Inactive);
+		// Also make sure to de-dupe if a session is re-intialized. In case of EH debugging we are adding a session again after an attach.
+		this.sessions = this.sessions.filter(s => s.state !== State.Inactive && s.getId() !== session.getId());
 		this.sessions.push(session);
 		this._onDidChangeCallStack.fire();
 	}