Hello orange2005,

At first, please check whether your original files are not merely hidden by the infection. More information on how to display hidden files can be found here.
If you find your files, simply remove all the detected Trojan horse files and remove the "hidden" attribute from your files. That could be done as follows:
1. Select all the files you want to remove the "hidden" attribute from.
2. Right click one of the files (while the files are still selected).
3. Select Properties.
4. Under Attributes, untick the Hidden item and click OK.

To make sure the infection is completely removed, we strongly recommend running thorough AVG full computer scan as described here.

If it is not possible to find your original files, it is likely we can't recover them. However, I can't tell for sure; to be able to analyze the issue in details, we need diagnostic data from your computer. Please either contact AVG customer care experts or describe the issue in AVG Forums.

Thank you.