O365 Migration Endpoint Creation Error

When creating a migration endpoint you may receive the error that "No MRSProxy was found running at 'name.domain.com'" with the name of your email server from autodiscover.  If you check the EWS virtual directory you will see that in fact the MRSProxy is enabled.  Further, if you check the application event log on the Exchange server you will see Event ID 1309 from Source ASP.NET.  This was a very frustrating error as it prevented the creation of migration endpoints on either the Exchange on-prem or online side of the equation.  Luckily I came across this thread which explained that it's necessary to  recycle the MSExchangeServicesAppPool on the on-prem Exchange server.  This was a quick fix with no observable impact to users.  After performing this step migration endpoint creation was quick and painless.