Troubleshooting FileMaker Database Encryption Issues

Source: https://davidhamann.de/2018/08/19/fix-error-853-when-encrypting-filemaker-databases/

Have you ever gotten the following error after trying to encrypt your FileMaker databases?

Due to an error encountered, File encryption/decryption was skipped.  File:my_file.fmp12 [853]

Error 853 refers to One or more containers failed to transfer in the error code listing and herein usually lies the problem.

When you encrypt your database, make sure to place the existing external container data into the same folder as the database you want to encrypt. It is not enough to copy the RC_Data_FMS directory straight from the server. You need to have the external container data in a folder called Files.

Example structure:

├── my_file.fmp12
├── Files
│   └── my_file
│       └── Secure
│           ├── 73
│           │   └── 56
│           │       └── D73B1271
│           │           └── 3E64CD08
│           │               └── 3758AC5A
│           │                   └── 8BDD
│           ├── 9D
│           │   └── 49
│           │       └── 1B944C71
│           │           └── 2431FA23
│           │               └── 4D040845
│           │                   └── 6FCC
│           └── DD
│               └── CA
│                   └── CA860447
│                       └── 531EDF57
│                           └── B72C09FE
│                               └── 120A

Having a structure like this will most likely solve your error 853.