I know this is a dumb question but how do I set an environment variable?

Well, it really depends how you start Boinc Manager.
I use KDE and have a shortcut on my side panel with the command I gave earlier.
That method would also work if you start boincmgr from any shortcut.

Other than that, you could try adding export BROWSER=path_to_your_browser into your .bashrc
To find the path to my browser, I would type which firefox which would return /usr/bin/firefox so I could put export BROWSER=/usr/bin/firefox in my .bashrc

I edited the file BOINC/run_manager as below, adding the browser declaration to the beginning of the line. Works from desktop shortcuts now.

export BROWSER=/usr/bin/firefox && cd "/home/ken/BOINC" && exec ./boincmgr $@

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I know this is a dumb question but how do I set an environment variable?

Well, it really depends how you start Boinc Manager.
I use KDE and have a shortcut on my side panel with the command I gave earlier.
That method would also work if you start boincmgr from any shortcut.

Other than that, you could try adding export BROWSER=path_to_your_browser into your .bashrc
To find the path to my browser, I would type which firefox which would return /usr/bin/firefox so I could put export BROWSER=/usr/bin/firefox in my .bashrc

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For your 1st question you need to set an environment variable to point to your chosen browser ie export BROWSER=/opt/mozilla/mozilla
I amended the shortcut to boincmgr to something like this
export BROWSER=/opt/mozilla/mozilla; cd /home/boinc; boincmgr

I know this is a dumb question but how do I set an environment variable?

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For your 1st question you need to set an environment variable to point to your chosen browser ie export BROWSER=/opt/mozilla/mozilla
I amended the shortcut to boincmgr to something like this
export BROWSER=/opt/mozilla/mozilla; cd /home/boinc; boincmgr

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I run the Boinc manager and specify setiathome when it asks for url--- so far so good- I become attached and it appears to be downloading a work unit?--- Anyway, every time I click on BOINC menu- " YOUR ACCOUNT" or "Preferences" or whatever I get error message "Must specify default browser..etc" then am directed to seti/home.php - there is no where on this pref list to specify a browser.
Also- when I close BOINC and try to open again I have to respecify URL to attach to..I need BOINC for dummies!!!

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