TaxCloud says it has recovered from a May 31 attack on its online system that left it with a 23-hour outage. The company, which offers free Internet-based sales tax software, reported on its website the intrusion and steps it took to recover and prevent another attack. The TaxCloud website said the attack happened at 6:02 pm. that day and describes it as "calculated and malicious." A status page says service was restored on June 1 at 5:18 pm EDT.