A digital security architect on Monday evening discovered several weaknesses in the Trump Organization’s email servers, which appeared to be outdated and not patched for security flaws.

“There are no security fixes. They don’t have basics down,” Kevin Beaumont said on Twitter, noting several problems with the machines that run email for the Republican presidential nominee’s hotels, golf courses and other businesses.

According to Beaumont, Trump is running Windows Server 2003, which Microsoft has not supported for more than a year.

“If you are still running Windows Server 2003 in your datacenter, you need to take steps now to plan and execute a migration strategy to protect your infrastructure,” the company claims on its website.