Some time ago I got this error when building ANY Visual Studio Deployment project.
"Unrecoverable build error"
I thought my VS installation was corrupted or I deleted some important files, but ...
...all I had to do was.
Close down Visual Studio.
Start, Run or WIN+R, type cmd, OK.
regsvr32 "C:\Program Files\Common Files\Microsoft Shared\MSI Tools\mergemod.dll"
regsvr32 ole32.dll
For x64 bit machines
regsvr32 "C:\Program Files (x86)\Common Files\Microsoft Shared\MSI Tools\mergemod.dll"
regsvr32 ole32.dll
Warning: you MUST run the command prompt in Admin Mode!
Close Command Prompt.
Open up Visual Studio and try rebuilding your deployment project! It worked for me!