I am using MSSQLServer 2008 and I got the same error (Package 'Microsoft SQL Server Management Studio' failed to load) since last couple of days.
I tried with this solution
C:\Users\romah>start /wait f:\setup.exe /qb REINSTALL=SQL_Tools100 REINSTALLMODE=OMUS
but it says
TITLE: SQL Server Setup failure.
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SQL Server Setup has encountered the following error:
The syntax of argument "/QB" is incorrect. Either the delimiter '=' is missing or there is one or more space characters before the delimiter '='. Please use /? to check usage.
Error code 0x84B40001.
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