If you try installing the .Net framework from the add feature in Server Manager on Server 2012 chances are that you’ll get an error.
Instead, put the cd (or ISO) on the drive, open the command prompt and type:
dism.exe /online /enable-feature /all /featurename:NetFX3 /Source:(driveletter)\sources\sxs /LimitAccess
The /all is important as it will install the parent features as well.
I recently ran in to a bit of a headache.
I had to reinstall a machine that already had a BitLocker encrypted disk.
The installation went smoothly, using Windows Deployment Services everything worked fine, until I had to encrypt the disk.
BitLocker was unable to detect the TPM module even though it was activated.
I tried to go into the BIOS, clear the TPM, deactivate it and restart. Then re-activate it and restart.
Even the TPM MMC snap-in was unable to detect the module .
Resolution: Go in the Device Manager and remove all devices that smells of TPM and restart.
I my case it was the TPM module under “Security Devices” and a TPM entry under “System Devices”.
Funny thing is that the one under “System Devices” never reappeared. But Windows found the TPM module and BitLocker encrypted the drive.