| Value | Error Code | Description |
| 1 | F_ERR_RESERVED_1 | The specified drive does not exist. |
| 2 | F_ERR_NOTFORMATTED | The volume is not formatted. |
| 3 | F_ERR_INVALIDDIR | The directory specified is not valid. |
| 4 | F_ERR_INVALIDNAME | The file name specified is not valid. |
| 5 | F_ERR_NOTFOUND | The file or directory could not be found. |
| 6 | F_ERR_DUPLICATED | The file or directory already exists. |
| 7 | F_ERR_NOMOREENTRY | The volume is full. |
| 8 | F_ERR_NOTOPEN | A function cannot complete because the file is not open. |
| 9 | F_ERR_EOF | End of file. |
| 10 | F_ERR_RESERVED_2 | Not used. |
| 11 | F_ERR_NOTUSEABLE | An invalid parameter was passed into f_seek(). |
| 12 | F_ERR_LOCKED | The file is already opened for writing / appending. |
| 13 | F_ERR_ACCESSDENIED | The necessary physical read and/or write functions are not available for the volume. |
| 14 | F_ERR_NOTEMPTY | The directory cannot be deleted because it is not empty. |
| 15 | F_ERR_INITFUNC | No init function is available for the driver, or the function generated an error. |
| 16 | F_ERR_CARDREMOVED | The card is not present. |
| 17 | F_ERR_ONDRIVE | There is a non-recoverable error on the drive. |
| 18 | F_ERR_INVALIDSECTOR | A sector has developed an error. |
| 19 | F_ERR_READ | There was an error when reading the volume. |
| 20 | F_ERR_WRITE | There was an error when writing to the volume. |
| 21 | F_ERR_INVALIDMEDIA | The media is not recognised. |
| 22 | F_ERR_BUSY | The access semaphore was not obtained before the timeout expired. |
| 24 | F_ERR_INVFATTYPE | The FAT type is not recognised. |
| 25 | F_ERR_MEDIATOOSMALL | Media is too small for the type of format requested. |
| 26 | F_ERR_MEDIATOOLARGE | Media is too big for the type of format requested. |
| 27 | F_ERR_NOTSUPPSECTORSIZE | The sector size is not supported. The only supported sector size is 512 bytes. |
| 28 | F_ERR_ALLOCATION | There was a memory allocation error. |