The instance health check spins incessantly in IE11
Launch Confluence 6.0.5 in IE 11
Navigate to Confluence Administration > Support Tools > Instance Health
IE version 11.0.9600.18524
The health checks run, and the spinner disappears
The health checks run, but the spinner remains. In some cases, the health checks fail to run.
Use another browser
Generate a support zip, which will export the healthcheck results to a text file:
> General Configuration > Support tools
Go to the Create Support Zip tab
Uncheck all options except "Healthcheck results"
Click Create zip to create a zipped text file of the healthcheck results, then follow the link to download.