[TYPO3-UG US] Warning: Unable to fork

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3.7.0/t3lib/class.t3lib_stdgraphic.php on line 2376
Warning: Unable to fork [/home/webadmin/typo3-usa.com/html/typo3_src-3.7.0/imagemagick-4.2.9/bin/convert -geometry 19x18! -colors 64 typo3/ext/tt_rating/pi/star_mask.gif[0] typo3temp/pics/7cffc7dd92.png] in /home/webadmin/typo3-usa.com/html/typo3_src-
3.7.0/t3lib/class.t3lib_stdgraphic.php on line 2376
Warning: Unable to fork [/home/webadmin/typo3-usa.com/html/typo3_src-3.7.0/imagemagick-4.2.9/bin/convert -geometry 19x18! -colors 64 typo3/ext/tt_rating/pi/star.gif[0] typo3temp/pics/4db64c6b1d.png] in /home/webadmin/typo3-usa.com/html/typo3_src-
3.7.0/t3lib/class.t3lib_stdgraphic.php on line 2376
Warning: Cannot add header information - headers already sent by (output started at /home/webadmin/typo3-usa.com/html/typo3_src-3.7.0/t3lib/class.t3lib_stdgraphic.php:2376) in /home/webadmin/typo3-usa.com/html/typo3_src-
3.7.0/typo3/sysext/cms/tslib/class.tslib_fe.php on line 2411