admin backend icon fonts missing

Open up app/etc/di.xml find the path

Magento\Framework\App\View\Asset\MaterializationStrategy\Symlink

and replace it with

Magento\Framework\App\View\Asset\MaterializationStrategy\Copy

Note: Remove entire files and folder under pub/static except .htaccess

It seems that some css and fonts files are not generated properly. You need to do the folowing

1. Remove pub/static
2. Remove var/cache
3. Remove var/composer_home
4. Remove var/generation
5. Remove var/page_cache
6. Remove var/view_preprocessed
7. run php bin/magento setup:static-content:deploy

Open up app/etc/di.xml find the path

Magento\Framework\App\View\Asset\MaterializationStrategy\Symlink

and replace it with

Magento\Framework\App\View\Asset\MaterializationStrategy\Copy

Then go to var\cache this folder remove all file