Upon further investigation, I found that creating /var/cache/software-center/xapian and making it world writeable does the trick. However, I don't think it should need to do that. I think aptdaemon should be handling that, so perhaps the root cause is aptdaemon failure.
Upon further investigation, I found that creating /var/cache/ software- center/ xapian and making it world writeable does the trick. However, I don't think it should need to do that. I think aptdaemon should be handling that, so perhaps the root cause is aptdaemon failure.