Q: Can I recover deleted files and or directories?
A: Unfortunately, the most likely answer is “you can't”. Second most likely is “Maybe, with infinite time and finances”. There are a few options for data recovery. R-Studio - Available here - is one many people report success with. Read this topic for important info: Fatal Trap 12 on XigmaNAS causes Restart when accessing Raid5.
You can also try UFS Explorer.
Then there are a few other alternatives reviewed in Five Best Free Data Recovery Tools:
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