SOLVED Can't install BOINC Manager

I am trying to reinstall the BOINC manager onto my desktop, although I am having some trouble. I am trying to install it on the G: external drive, which can be seen on the first image. However, when I click next then it complains that my disk drive does not have enough space? Why is this happening? (Second image).

This results in the error "Error 2803. Dialog View did not find a record for the dialog NoDialog".

I don't know how to proceed from here, so any help would be great!

Try keeping the directories separate instead of installing BOINC in one directory (G:\BOINC), running the Data directory as a sub-directory of the BOINC directory (G:\BOINC\Data\). Instead try setting the Program directory as G:\BOINC, and the Data directory as G:\BOINC Data?

Managed to fix it by using my phone in USB mode to be assigned F: just whilst it installed, even though it never installed anything on it - this is with the same directories I originally made but thanks for the suggestion!