If you can no longer open your logbook after an iOS update, your FileMaker Go version (not the logbook itself) is probably out of date.
The logbook datafile ‘logbook9.fmp12’ runs on all versions of FileMaker Go (12-16) but, iOS 11 has been designed to run only 64-bit apps and so Apple have effectively abandoned ship on older 32-bit versions of the app. FileMaker Go versions 15 (released March 2017) and 16 (released July 2017) are 64-bit, and so continue to work fine after the iOS 11 upgrade.
- Go to the App store. Search for the new 64-bit version (16) of FileMaker Go as it will have been distributed as a different app.
- Install it to your iOS device.
- Then use either iTunes or iMazing (https://imazing.com/download) to get the ‘logbook9.fmp12’ file off the old FileMaker Go app on your iPhone, and onto a laptop/desktop computer.
- Email the ‘logbook9.fmp12’ file to yourself as an email attachment.
- Open the email on your iPhone after you have installed the newest version of Filemaker Go, and the mail app will offer you the option to install it to the new FMGo version.
For more info on moving files see: http://tinyurl.com/oldFMGo-version