Here are the following methods on retrieving data from Single bay systems, or RAID 1-volumes
The best defense is to backup your data, and I remind all users to backup their data periodically, less you want to have data loss
This method will require addtional hardware, a SATA/PATA--->USB Enclosure, and another HDD. The second HDD can be an old HDD, such as a 4GiB collecting dust in the closet.
For the sake of this discussion, it the second HDD will be called HDD_B, while the original drive will be labed HDD_A
1. Power down the DS
2. Remove HDD_A
3. Install HDD_B
4. Powerup the system, and install the latest firmware using the latest Synology Assistant (available in my signature)
5. Once the install is completed, Install HDD_A into the USB Enclosure
6. Power up the enclosure, and plug it in the DS
7. It will be recognized as \\diskstation\usbshare1
8. Retrieve your data
9. Remove HDD_A from the enclosure, and sanitize it
10. Power down the DS
11. Remove HDD_B, and install HDD_A
12. Install the firmware package.
Note: this method will only work for systems which have performed a clean install of version 25x or above
If you are using an older firmware, or have not performed a clean install, please use method 2
1. Download explore2fs, a ext3 file system reader for Windows
2. Remove HDD_A from the DS
3. Install it in a Windows PC
4. Use explore2fs to view your data
Please contact online support, with your forum thread if neither of these methods yeild fruitful results, or you have a 4-drive question.