Please let me know the following details:
1. Which version of Adobe Reader are you using. Is it 10.1.0 or 10.1.1 or 10.1.2?
2. What is the exact error message received. Could you post a screenshot of the same.
3. Have you tried removing any external Reader font packs (such as Japanese/Chinese etc) installed on your system separately. You can try and remove the same using the Add/Remove Programs from witin the Control Panel.