Hello, & Welcome to Tom's Hardware!
Please try to be a lot more specific about the problem you are having. Is this an older external HDD? Used for backup or a data store? Has it been working normally, and what has happened to make it not function properly.
What kind of error message to you get, if any, when you try to use it?
Can you read and write data to the HDD without using the one touch button?
That way, someone will be able to help.