First the government shuts them out of their offices. Now, a corporate vendor has robbed congressional staffers of sleep and rendered their inboxes unnavigable.

According to various House aides the latest affront happened early Tuesday morning, when an introductory email from 4PIA CEO Rani Yadav-Ranjan wreaked havoc on the Hill.

The cookie-cutter message, one would assume, was intended to plug the product (a daily report about Twitter mentions and related social media activity) by showcasing a custom report for each individual member of Congress.

The only problem is that the company sent EACH report to EVERY member office.

“We got hit with 500-something emails, each one directed to a different [representative] or senator. They starting dinging on my BlackBerry and woke me up at 2:00 this morning, and I had to silence the ringer before I could get back to sleep,” one Democratic aide said of the disruptive experience.

“It was unreal,” affirmed a GOP aide, who said the deluge created a serious backlog in the office. “Nothing like going to bed and waking up to 600 unread email messages.”

A 4PIA aide offered no explanation for the spam surge.

“We tested this system multiple times without a glitch,” the appointment setter assured HOH. “Our tech teams are still trying to understand what happened.”

To wit, the 4PIA aide said some offices had taken the bait and signed up for the service.

“Would Roll Call like to be on the list?” the shameless saleslady inquired.

No thanks. We have enough trouble sleeping already.