Error exporting content.

Hi,
I think this is support to the export tool for wordpress

I have a lot of trouble trying to make this task.

THe file is downloaded but only an error is showing

<br />
<b>Fatal error</b>:  Unknown: Cannot use output buffering in output buffering display handlers in <b>Unknown</b> on line <b>0</b><br />

I already change the memory to 256 in the wp_config.php

Please help me.

Thanks