为什么好些下载无效？

qianhongUID: 137206

总是出现<br>
<b>Warning</b>:  stat failed for attachment/64183_1053634520.gif (errno=2 - No such file or directory) in <b>/home/bbs/web/bbs/attachment.php</b> on line <b>77</b><br>
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<b>Warning</b>:  Cannot add header information - headers already sent by (output started at /home/bbs/web/bbs/attachment.php:77) in <b>/home/bbs/web/bbs/attachment.php</b> on line <b>77</b><br>
<br>
<b>Warning</b>:  Cannot add header information - headers already sent by (output started at /home/bbs/web/bbs/attachment.php:77) in <b>/home/bbs/web/bbs/attachment.php</b> on line <b>78</b><br>