I am trying to remove Boinc from my computer.
I go to add/remove programs, then choose Boinc.

It starts to uninstall the program, then I get a pop-up window that says:

"The feature you are trying to use is on a network resource that is unavailable.

Click OK to try again, or enter an alternate path to a folder containing the installation package 'BOINC.msi' in the box below.

Use source:
C:\Users\[MY NAME]\Downloads\ (with a button to browse)"

I tried to search my computer for BOINC.msi and it can't find it anywhere.

Can anybody help me?

That's what we call a corrupt installer. See this FAQ for ways around it.

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