Installing Windows Server 2012 on a VMware ESXi 5.1 hypervisor throws the error message: “A media driver your computer needs is missing. This could be a DVD, USB or Hard disk driver…”

A colleague of mine recently reached out to me about an issue while installing Windows Server 2012 on a VMware ESXi 5.1 hypervisor where he would receive the following error message:

A media driver your computer needs is missing. This could be a DVD, USB or Hard disk driver. If you have a CD, DVD, or USB flash drive with the driver on it, please inesrt it now.

Note: If the installation media for Windows is in the DVD drive or on a USB drive, you can safely remove it for this step.

Hide drivers that aren’t compatible with this computer’s hardware.

I recall running into a similar issue with Windows Server 2008 R2 before where an error similar to the above was thrown when an incomplete or corrupted ISO was used for the install so I asked him to compare the file sizes between his download and one that I had on my laptop and we immediately noticed that the sizes were different:

Bad ISO:

Name: SW_DVD5_Win_Svr_Std_and_DataCtr_2012_64Bit_English_Core_MLF_X18-27588.ISO
File Size: 2,635,776 KB

Good ISO:

Name: SW_DVD5_Win_Svr_Std_and_DataCtr_2012_64Bit_English_Core_MLF_X18-27588.ISO
File Size: 3,607,534 KB

Basically what happened with his download was that an inspection module on firewalls he initiated the download from caused his download to be partly downloaded while the download manager suggested it was completed.  My guess is that the ISO wasn’t semi readable and therefore the install kicked off but when the drivers required were missing, the install would not continue.  What I ended up doing was giving him the ISO I had to try the install again and the install completed as expected.