Depends on what's broken.
The only thing you can try yourself:
Put the disk in another enclosure. This should work if the error was strictly in the enclosure and didn't propagate to the disk.
If this fails (and it seems it did), it's a job for a data recovery company. You will only lose those files that you don't have a backup for. That is, only unimportant files. You did backup important files, did you? That's really necessary, not only for the usual data on an internal hard disk, but even more for data on an external disk, because those are so much less reliable.
Kees
I have a simpletech 320 gb external hard drive, I plugged it up and the connector board heated up and it shut down my computer. I tried another casing it wants to boot up but then shuts down. What can I do to retract the data?

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