had level 2 QB support tell me that if a user is hosting, it can mess wit the sharing from the server for the rest of the lan. wrote a quick-n-dirty PS script to look for qb hosting on the clients. mind you, it is not as easy as turning off the service on the machines, have to do it from quickbooks on their pc. this spits out who has hosting on, no responce == good. save below into a file with .ps1 extension. and make sure you have "Set-ExecutionPolicy RemoteSigned"
$Servers = @("pcname1","pcname2l","pcname3",
"pcname5","pcname6")
for ($i = 0; $i -le $Servers.length -1; $i++){
$qbService = Get-Service -Name QuickBooksD* -ComputerName $Servers[$i] | where { $_.status -eq 'running' }
if ($null -ne $qbService){
write-Host $Servers[$i]
echo $qbService}