Writing in an excel file did not work proper

hi,

i had wrote the following code:

<a class="attachment" href="/uploads/default/original/3X/c/3/c3043f05ebc0fddc9ffdbe0092cf4368fbf309e7.xaml">Main.xaml</a> (17.4 KB)

but i see the values wrotten in the excel file but int the end file is empty!!!