Error en php

[Matthew_182]

Ise una pagina llamada php.php y al abrirla en el navegador solo sale

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<b>Warning</b>: fopen(): Unable to access datos.txt in <b>/home/webcindario/webexperto/php.php</b> on line <b>23</b><br />
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<b>Warning</b>: fopen(datos.txt): failed to open stream: No such file or directory in <b>/home/webcindario/webexperto/php.php</b> on line <b>23</b><br />
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<b>Warning</b>: filesize(): Stat failed for datos.txt (errno=2 - No such file or directory) in <b>/home/webcindario/webexperto/php.php</b> on line <b>25</b><br />
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<b>Warning</b>: fread(): supplied argument is not a valid stream resource in <b>/home/webcindario/webexperto/php.php</b> on line <b>25</b><br />
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<b>Warning</b>: fclose(): supplied argument is not a valid stream resource in <b>/home/webcindario/webexperto/php.php</b> on line <b>26</b><br />
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<b>Fatal error</b>: Maximum execution time of 5 seconds exceeded in <b>/home/webcindario/webexperto/php.php</b> on line <b>28</b><br />

xq pasa? saludos