# When first run D5, why prompt 'Cannot continue executing code because Qt5Core.dll was not found.'

<figure class="doc-image doc-image--stack">
  <img src="https://docs-static.d5render.com/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces/-MjbN1iGmN_HBnj_fyU9/uploads/OIKEz2bWSpLNlT5HD9Mq/image.png" alt="Qt5Core.dll" />
  <figcaption>Qt5Core.dll</figcaption>
</figure>

It may be caused by the following: 

  1. The download package is incomplete, we recommend using Chrome or edge browser to download.

  2. Third-party decompression software lost files during decompression. We recommend using Windows official decompression or 7-zip.

  3. There is no permission for the current directory where D5 is installed. When confirming the change of installation, install on a different disk.