Malicious software spreading, Microsoft reports

The amount of so-called malware and other unwanted software rose 43 percent in the first half of the year. The software can open gateways for hackers and identity thieves.

Microsoft said that there are a number of steps that computer users can take to help protect their systems.

First, frequently check for and apply security updates, including updates from third-party application providers.

Next, make sure your firewall is enabled and install up-to-date antivirus and anti-spyware programs.

Also, use caution when opening links and attachments embedded in e-mails. Hackers often use links to direct users to phony web sites in a technique called phishing.

A copy of Microsoft's latest Security Intelligence Report is available for download.