TYPO3 Core

With tt_news installed update to 4.7beta1 fails. The frontend shows:

===
Fatal error: require_once() [function.require]: Failed opening required '/home/tackhead/domains/tackhead.com/public_html/t3lib/class.t3lib_htmlmail.php' (include_path='.:/usr/local/lib/php') in /home/tackhead/domains/tackhead.com/public_html/typo3conf/ext/tt_news/pi/class.tx_ttnews.php on line 44 ===

and after a refresh .....

===
Uncaught TYPO3 Exception
#1294587218: No TypoScript template found! (More information)

t3lib_error_http_ServiceUnavailableException thrown in file
/home/typo3_src/typo3_src-4.7.0beta1/typo3/sysext/cms/tslib/class.tslib_fe.php in line 2116.

2 tslib_fe::getConfigArray()

/home/typo3_src/typo3_src-4.7.0beta1/typo3/sysext/cms/tslib/index_ts.php:
00317: // After this, we should have a valid config-array ready
00318: // **********************************************
00319: $TSFE->getConfigArray();
00320:
00321: // ************************

1 require("/home/typo3_src/typo3_src-4.7.0beta1/typo3/sysext/cms/tslib/index_ts.php")

/home/typo3_src/typo3_src-4.7.0beta1/index.php:
00076: // **********
00077:
00078: require (PATH_tslib.'index_ts.php');
00079:
00080: ?> ===

De-installing tt_news solves the problem. Of course I do not want a site without tt_news.