I figured out how to use handle.exe, but I can't use msizap because I don't have that Windows SDK Components thing, and when I try to install it I get an error saying "Unable to load Jit Compiler: (mscorjit.dll): file may be missing or corrupt. Please check or rerun setup." I found something else called kill.exe that did end the process after I found its handle, but msiexec.exe always starts back up after I kill it...
Here's what I see when I typed "handle msiexec"
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msiexec.exe pid: 2508 NT AUTHORITY\SYSTEM
C: File (RW-) C:\WINDOWS\system32
60: File (RW-) C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-Controls_6595b64144ccf1df_6.0.2600.2982_x-ww_ac3f9c03
64: File (RW-) C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-Controls_6595b64144ccf1df_6.0.2600.2982_x-ww_ac3f9c03
6C: Section \BaseNamedObjects\AutoUnhookMap$000009cc$10000000
90: Section \BaseNamedObjects\NamedBuffer, mAH, Process $000009cc, API $7c802367
94: Section \BaseNamedObjects\NamedBuffer, mAH, Process $000009cc, API $7c801af1
9C: Section \BaseNamedObjects\NamedBuffer, mAH, Process $000009cc, API $7c802332
A0: Section \BaseNamedObjects\NamedBuffer, mAH, Process $000009cc, API $7c86136d
178: Section \BaseNamedObjects\DFMap0-325597148
190: Section \BaseNamedObjects\DfRoot013683A4C
1E4: Section \BaseNamedObjects\ShimSharedMemory
234: File (R--) C:\WINDOWS\Installer\25c844.msi
434: Section \BaseNamedObjects\DFMap0-325597770
460: File (R--) C:\WINDOWS\Installer\457ce99.mst
494: Section \BaseNamedObjects\DfRoot0136837DE
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msiexec.exe pid: 2648 NT AUTHORITY\SYSTEM
C: File (RW-) C:\WINDOWS\system32
60: File (RW-) C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-Controls_6595b64144ccf1df_6.0.2600.2982_x-ww_ac3f9c03
64: File (RW-) C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-Controls_6595b64144ccf1df_6.0.2600.2982_x-ww_ac3f9c03
6C: Section \BaseNamedObjects\AutoUnhookMap$00000a58$10000000
90: Section \BaseNamedObjects\NamedBuffer, mAH, Process $00000a58, API $7c802332
94: Section \BaseNamedObjects\NamedBuffer, mAH, Process $00000a58, API $7c801af1
98: Section \BaseNamedObjects\NamedBuffer, mAH, Process $00000a58, API $7c802367
A0: Section \BaseNamedObjects\NamedBuffer, mAH, Process $00000a58, API$7c86136d
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