This is caused by a setting in Adobe Reader that wants to open the .pdf in Adobe and not in your internet browser. Here are the steps to fix this setting:
1. Open Adobe Reader
2. Click on Edit in the Menu Bar
3. Choose Preferences
4. Along the left hand side choose the internet category
5. Make sure the check box is checked for "open PDF in browser"
1. Open Adobe Reader
2. Click on Edit in the Menu Bar
3. Choose Preferences
4. Along the left hand side choose the internet category
5. Make sure the check box is checked for "open PDF in browser"