[TYPO3] Cannot modify header information error

[Jozef Uhliarik]

I am newbie in TYPO3. I moved a content from my local server to Internet. I 
changed charset of database from latin1 to utf8 too. Now some errors 
appears. After clear caches all is OK but refresh or a look to subpages is 
bad.

Warning: reset() [function.reset]: Passed variable is not an array or object 
in 
/home/clients/ztsnam.sk/typo3_src-4.0/typo3/sysext/cms/tslib/class.tslib_content.php 
on line 2997

Warning: Variable passed to each() is not an array or object in 
/home/clients/ztsnam.sk/typo3_src-4.0/typo3/sysext/cms/tslib/class.tslib_content.php 
on line 3000

Warning: Cannot modify header information - headers already sent by (output 
started at 
/home/clients/ztsnam.sk/typo3_src-4.0/typo3/sysext/cms/tslib/class.tslib_content.php:2997) 
in 
/home/clients/ztsnam.sk/typo3_src-4.0/typo3/sysext/cms/tslib/class.tslib_fe.php 
on line 2767