The TAG thoracic endograft is a commercially available device used for endovascular repair of thoracic aneurysms. It has a single-action deployment mechanism, similar to its abdominal counterpart, consisting of an expanded polytetrafluoroethylene string, which is used to constrain the self-expanding stent graft within an integral external expanded polytetrafluoroethylene corset. This report describes two cases of deployment failure of the TAG device and the bailout techniques used to correct the problem and complete the procedure. In one case, this complication resulted in a devastating intraoperative stroke that led to the death of the patient. Although this is an extremely rare occurrence, the rapid recognition of the problem and ability to correct it by using catheter-based techniques are important during endovascular treatment of thoracic aortic diseases using the TAG device.