If you have a file named something like "Jnjnojnon..." and it is a .rar file you cannot open, you are likely dealing with a filename encoding issue or a corrupted archive.
If this was a major typo regarding and perhaps a "Rare" (rar) condition or stock event: Jnjnojnonäono rar
However, based on the suffix and the keyboard patterns, there are two likely scenarios for what you're looking for. 1. If this is a corrupted file or an archive error If you have a file named something like "Jnjnojnon