NEW YORK (

TheStreet

) --

HP

(HPQ) - Get Report

missed Wall Street's revenue forecast, hurt by its PC and printer businesses. The No. 1 PC maker also lowered its guidance because of a weak global economy.

The tech giant reported revenue of $29.7 billion, down from $31.2 billion in the same period last year, and below Wall Street's projection of $30.1 billion.

Excluding items, HP earned $1 a share, in line with its

pre-announcement

earlier this month, but down from $1.10 a share a year earlier.

For fiscal 2012, the company now expects earnings of $4.05 to $4.07 a share, at the low end of its previously provided outlook.

"HP is still in the early stages of a multi-year turnaround, and we're making decent progress despite the headwinds," CEO Meg Whitman said in a statement released after the market close

HP's results come hot on the heels of underwhelming

second-quarter numbers

from rival

Dell

(DELL) - Get Report

earlier this week. The no.2 PC maker missed Wall Street's top-line estimate for its second-quarter results on Tuesday and offered weak third-quarter guidance. The Round Rock, Texas-based company noted a "challenging" environment for PC sales," prompting speculation that HP could face the same issues.

Revenue from HP's Personal Systems Group (PSG) declined 10% in the third quarter, while Imaging and Printing Group (IPG) revenue was down 3%.

The tech giant's shares plunged 4.9% to $18.26 in extended trading.

--

Written by James Rogers in New York.

Follow @jamesjrogers

>To submit a news tip, send an email to:

tips@thestreet.com

.

Check out our new tech blog,

Tech Trends

. Follow TheStreet Tech

on your wireless devices