ESXi 4.0 Error attempting to install Windows 2008 R2 on Dell PowerEdge Server
Recently I was attempting to install a new copy of Windows 2008 R2 Standard Edition on a customer’s ESXi machine. Although I was currently running many different operating systems on the server, I was surprised to see that I could not install 2008. I received the error “0xc000035a Attempting to load a 64-bit application, however this cpu is not compatible with 64-bit mode”. After about 10 minutes of troubleshooting I realised that the problem was not in Windows 2008 or ESXi but rather in the Dell System BIOS. For some reason dell ships their servers with Intel VT Virtualisation Technology turned off! ESXi is unable to run 64bit operating systems without first turning on VT technology. I’m surprised I missed this, out of some coincidence all of the operating systems on the machine are 32-bit. That seems a bit perplexing to me that by default Dell disables this on their servers, it seems like it’d be a no brainer to turn it on. Perhaps for security purposes? If you have an answer, let me know in your comments!