From: Sam Steinhauser on
I accidently installed the 2010 32 bit Office RTM last week. It run very fast
and then I realized I didn't have the 64 bit version. I got the 64 bit
installed with some effort but it seemed to lag so I tried to go back to 32
bit again and now I am locked out of installing either version. It errors out
reporting a previous trial has been installed on this computer. How can I get
Office back on my system?

--
Sam
From: pip22 on

There's nothing wrong with using 32-bit Office on 64-bit Windows, you
should have left it there the first time you installed it.

Now there are entries in the Registry referring to both the 64-bit and
32-bit trial versions, and until they are all removed you won't get any
further.

Try running System Restore to go back to a date before you installed
them. That should restore a copy of the previous Registry data with no
Office references. Then check C:\Program Files and delete any Office
folders.

Do the same in C:\Users\<your account name>\AppData\Local
and in C:\Users\<your account name>\AppData\Roaming

Now try installing Office trial again but decide from the outset
whether you want to try 32-bit or 64-bit. You can't try them both on the
same PC so make up your mind first!