The underlying cause of your problem (getting tasks you don't want) is that your location settings (also known as venues) are set up wrong.
You have only one location set up, which is the default or "---" location. However, your computer is assigned to the "home" location. Since you haven't set up a "home" location, the server is sending you random tasks. On our website, you should change two settings to correct this.
1) Change your computer to the default ("---") location. Click on "Your account", click on "Computers on your account (View)", and then click on "Details" below your computer ID. This will bring up the page for your computer. Scroll down to the bottom and change the "Location" setting from "Home" to "---". Finally, click on the "Update" button.
2) Change your account's default location from "Home" to "---" so that any computers you add in the future are assigned to the correct location. Click on "Your account", click on "PrimeGrid preferences", and then scroll to the bottom and click on "Edit PrimeGrid preferences". Change the "Default computer location" setting from "Home" to "---". Then scroll all the way to the bottom. The last step is to click the "Update preferences" button, but before doing that, do the bonus step below.
bonus) Right above the "Update references" button is a checkbox labeled "Send work from any subproject if selected projects have no work". You have that box checked. You should turn it off. It's very unusual for us to be out of tasks, and if we are, it's only for a fraction of a second. You don't want to get random tasks. Turn this box off, and then click on "Update preferences".
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