Yahoo is angering the dwindling number of people who still use its email service with a test run of a feature that locks out anyone who has an ad blocker installed.<br />Several Yahoo users complained that they encountered an error message when trying to open their mail account on Thursday in an AdBlock Plus forum thread first spotted by Digiday .<br />Yahoo joins a growing number of media sites to experiment with barring ad block users altogether as the technology available to do so becomes more widespread.<br />New York Times CEO Mark Thompson also said in a recent earnings call that the paper is looking into "technical solutions" to combat blockers.
