You have to either remember how you did it before and if you lost a CD/DVD you may be out of luck.
I did google it and http://getintopc.com/softwares/education/oxford-talking-dictionary-free-download/ claims to have another way but for support you ask them how.
Hi,
I am unsuccessfully trying to run the Oxford Talking Dictionary. The reason is I installed it from a folder, and not from its own cd, and the folder I copied was from a DVD that had many other dictionaries on it as well. The DVD I used was not exclusively for this particular dictionary only. Previously, I always used this dictionary using its own cd, but that cd is not available in the market any more. So, I have to stick to this particular DVD which seems to be very much a compacted disk carrying the folders of several other dictionaries as well. In short, I am having trouble running the dictionary after installing it from its folder. The error message something like “insert the disk drive”. I have tried out virtual cd as well but to no avail. I guess I need to extract/create an icon/image of it first so that when I insert the dictionary folder into a virtual drive, it should appear like an image like before. Please guide me as to how to fix this.
Thanks
Nadeem.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic