I run three machines at home on a single dialup account running WCG on BOINC. At first it seemed confusing as to how to manage the transfers as the client appears to favor a dedicated connection.

To make a long story short, I now toggle Activity after connecting and disconnecting my phone line to the internet.

Unchecking/checking Run and Network Activity on and offline reduces the nag messages and makes running BOINC a bit more tidy on a dialup account.

Open BOINC Manager->Advanced view->Advanced->Options.
Set the "Notice reminder interval" slider to zero.

This will stop the nagging.

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