Turning on email notifications breaks MS Release Management - deployment

Question

I am running TFS 2013 Update 4, Release Management Client Update 4, Release Management Server Update 4, and Update 4 Deployment Agents. I am using ReleaseTfvcTemplate.12.xml.
When a developer checks in code, TFS Build compiles the code, and if it completes then it is released to the DEV stage. This works fine.
However, turning on emails creates a problem.
Let's say I need to notify 10 people of a deployment and then send those same 10 people "approval" emails after the deployment is accepted, which it automatically is. That's 20 emails.
I turned on verbose logging on the RM server and I see that each email takes 30 seconds to send. They send one at a time, one after the other. So it takes ten minutes to send twenty emails.
The emails start sending as soon as the deployment starts. The actual deployment usually takes around 1 minute. Release Management marks the build as deployed and keeps sending the "deploying" and "approval" emails. Meanwhile the TFS Build Configuration log is stuck waiting at:
Process each ConfigurationsToRelease
Release the build
Run the Release Management build process for the current configruation
If a deployment finishes its' emails because they are turned off or there are only 3-4 to send, then the TFS Build Configuration log completes the release and the build is marked successful. However, TFSBuild will only wait 5 minutes at the "Release the build" part of the ReleaseTfvcTemplate workflow. If it takes longer than 5 minutes to send 20 emails, which it does, the build fails. How do I increase this timeout? I have upped the timeout on every component/tool I could find in Release Management. I even changed some web.config timeout settings.
The end result is I end up with deployed code, Release Management thinks everything went fine, and TFS Build thinks the build failed.
Edit:
Here are some lines I pulled from the verbose RM server logs. Notice the timestamps. (I cut some lines out)
7/28/2015 3:49:48 PM - Verbose - (13008, 12024) - A workflow execution
is completed. 7/28/2015 3:49:48 PM - Information - (13008, 12024) -
DeploymentControllerServiceProcessor.OnActivityComplete: Workflow
completed successfully, accept the deployment step. LocalReleaseId:
596, LocalReleaseStepId: 2158 7/28/2015 3:54:47 PM - Information -
(13008, 6952) -
DeploymentControllerServiceProcessor.PrepareNotificationForDeployerImplementation:
NextActivityReadyForDeployment: 7/28/2015 3:54:47 PM - Information -
(13008, 6952) -
DeploymentControllerServiceProcessor.GetNextComponentReadyForDeployment:
DeploymentEvent: 7/28/2015 3:54:49 PM - Information - (13008, 12024)
- Exception in DeploymentControllerServiceProcessor.OnActivityComplete, app.Completed
7/28/2015 3:54:49 PM - Verbose - (13008, 12024) - The request was
aborted: The request was canceled.: \r\n\r\n at
System.Net.HttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
at
Microsoft.TeamFoundation.Release.Data.WebRequest.PlatformHttpClient.EndGetResponse(IAsyncResult
asyncResult) at
Microsoft.TeamFoundation.Release.Data.WebRequest.RestClientResponseRetriever.EndGetAsyncMemoryStreamFromResponse(IAsyncResult
asyncResult, IPlatformHttpClient platformHttpClient) at
Microsoft.TeamFoundation.Release.Data.WebRequest.RestClientResponseRetriever.EndDownloadString(IAsyncResult
asyncResult, IPlatformHttpClient platformHttpClient) at
Microsoft.TeamFoundation.Release.Data.WebRequest.RestClient.EndPost(IAsyncResult
asyncResult) at
Microsoft.TeamFoundation.Release.Data.Proxy.RestProxy.HttpRequestor.<>c__DisplayClass1.b__0(String
url, String body) at
Microsoft.TeamFoundation.Release.Data.Proxy.RestProxy.BaseNotificationServiceProxy.SendNotification(Int32
releaseId, String releaseName, String applicationVersionName, String
stageTypeName, String environmentName, Int32 releaseStepId, Int32
releaseStepTypeId, Boolean releaseStepIsAutomated) at
Microsoft.TeamFoundation.Release.Workflow.Services.ReleaseWorkflowService.CreateNextReleaseStep(Release
release, Stage stage, StageStep stageStep, Int32 releaseStageRank,
Int32 trialNumber) at
Microsoft.TeamFoundation.Release.Workflow.Services.ReleaseWorkflowService.MoveToNextReleaseStep(Release
release, Stage currentStage, ReleaseStep currentReleaseStep) at
Microsoft.TeamFoundation.Release.Workflow.Services.ReleaseWorkflowService.MoveWorkflowForward(Release
release, ReleasePath releasePath, Stage currentStage, ReleaseStep
currentReleaseStep, Int32 lastStepRankOfCurrentStage) at
Microsoft.TeamFoundation.Release.Workflow.Services.ReleaseWorkflowService.AcceptStep(Release
release, Int32 releaseStepId, Int32 actualApproverId, String
approverComment, Nullable1 deferredDateTime) at
Microsoft.TeamFoundation.Release.Workflow.Services.ReleaseWorkflowService.CreateNextReleaseStep(Release
release, Stage stage, StageStep stageStep, Int32 releaseStageRank,
Int32 trialNumber) at
Microsoft.TeamFoundation.Release.Workflow.Services.ReleaseWorkflowService.MoveToNextReleaseStep(Release
release, Stage currentStage, ReleaseStep currentReleaseStep) at
Microsoft.TeamFoundation.Release.Workflow.Services.ReleaseWorkflowService.MoveWorkflowForward(Release
release, ReleasePath releasePath, Stage currentStage, ReleaseStep
currentReleaseStep, Int32 lastStepRankOfCurrentStage) at
Microsoft.TeamFoundation.Release.Workflow.Services.ReleaseWorkflowService.AcceptStep(Release
release, Int32 releaseStepId, Int32 actualApproverId, String
approverComment, Nullable1 deferredDateTime) at
Microsoft.TeamFoundation.Release.ServiceProcessor.Processor.DeploymentControllerServiceProcessor.OnActivityComplete(String
workflow, WorkflowApplicationCompletedEventArgs e)

Answer 1

There is a setting on the "Administration" tab under "Settings" for "TFS Trigger Deployment Timeout". If you increase that, the build won't fail after 5 minutes.
I'd invest some time looking at why it takes 30 seconds to send each email, though. I've never seen that particular problem... it could be a network issue, or an issue with your mail server.