[First of all, it is very sad that BizSpark susbcription do not have any technical support, even to inform a error like this :-((( ]
Ok, well , the error, that occurs twice creating a VirtualMachine, so replicated:
{
  "error": {
    "code": "InvalidParameter",
    "target": "resourceGroupName",
    "message": "The entity name 'resourceGroupName' is invalid according to its validation rule: ^[^_\\W][\\w-._]{0,79}(?<![-.])$."
  }
}The reason, it is because my resource group is called _ReGr_MyName, but IT ALREADY EXIST !!! (indeed the rest of resources, like Public-Ip, Storage Accounts, etc, are already under that resource group)
so seems like validation rules are inconsistent across different resources
I can provide the Operation-Id or the TRacking-ID if necesary
But please, solve this short of issues, Azure should be an stable system
 
     
     
    
that I mean as a BUG – pGrnd Dec 02 '16 at 10:37