Are the ACE files actually there, or has your antivirus software deleted them (moved it/them to its virus vault/chest)?

Sometimes they are seen as a threat due to a false possitive (usually a trojan) and the AV will move them to its virus vault/chest to protect you.
If they are in the virus vault/chest you need to restore them to their original location, and add it/them to the AV exclusion list so it won't do that again.