Forum Discussion
Unable to remove session host "Session host not found"
- Mar 12, 2020This worked for me and in this order. Add-RdsAccount -DeploymentUrl "https://rdbroker.wvd.microsoft.com"
 Set-RdsHostPool -TenantName $myTenantName -Name "contosoHostPool" -ValidationEnv $trueAdd-RdsAccount -DeploymentUrl "https://rdbroker-r0.wvd.microsoft.com"
Ben79 for whatever reason Microsoft has blocked the domain suffix 'ad' in their WVD deployment so you have to open a case any time you want to delete a Session host that uses that DNS suffix.
To speed things up reference Bug ID: 23462425
Here's the complete list of blocked suffixes in case it helps others:
<add fileExtension=".asa" allowed="false" />
<add fileExtension=".asax" allowed="false" />
<add fileExtension=".ascx" allowed="false" />
<add fileExtension=".master" allowed="false" />
<add fileExtension=".skin" allowed="false" />
<add fileExtension=".browser" allowed="false" />
<add fileExtension=".sitemap" allowed="false" />
<add fileExtension=".config" allowed="false" />
<add fileExtension=".cs" allowed="false" />
<add fileExtension=".csproj" allowed="false" />
<add fileExtension=".vb" allowed="false" />
<add fileExtension=".vbproj" allowed="false" />
<add fileExtension=".webinfo" allowed="false" />
<add fileExtension=".licx" allowed="false" />
<add fileExtension=".resx" allowed="false" />
<add fileExtension=".resources" allowed="false" />
<add fileExtension=".mdb" allowed="false" />
<add fileExtension=".vjsproj" allowed="false" />
<add fileExtension=".java" allowed="false" />
<add fileExtension=".jsl" allowed="false" />
<add fileExtension=".ldb" allowed="false" />
<add fileExtension=".dsdgm" allowed="false" />
<add fileExtension=".ssdgm" allowed="false" />
<add fileExtension=".lsad" allowed="false" />
<add fileExtension=".ssmap" allowed="false" />
<add fileExtension=".cd" allowed="false" />
<add fileExtension=".dsprototype" allowed="false" />
<add fileExtension=".lsaprototype" allowed="false" />
<add fileExtension=".sdm" allowed="false" />
<add fileExtension=".sdmDocument" allowed="false" />
<add fileExtension=".mdf" allowed="false" />
<add fileExtension=".ldf" allowed="false" />
<add fileExtension=".ad" allowed="false" />
<add fileExtension=".dd" allowed="false" />
<add fileExtension=".ldd" allowed="false" />
<add fileExtension=".sd" allowed="false" />
<add fileExtension=".adprototype" allowed="false" />
<add fileExtension=".lddprototype" allowed="false" />
<add fileExtension=".exclude" allowed="false" />
<add fileExtension=".refresh" allowed="false" />
<add fileExtension=".compiled" allowed="false" />
<add fileExtension=".msgx" allowed="false" />
<add fileExtension=".vsdisco" allowed="false" />
<add fileExtension=".rules" allowed="false" />
This worked for me and in this order. 
Set-RdsHostPool -TenantName $myTenantName -Name "contosoHostPool" -ValidationEnv $true