For support or others to be able to help you, you may need to provide some more information.
What version and build of Moneydance are you running. See under HELP – ABOUT MONEYDANCE. for example, I am running 2017.8(1682).
What OS is your computers running? If Mac did you purchase direct or through Apply.
What syncing method are you using Dropbox folder or Dropbox Connection.
Have you tried restoring from your Moneydance backups. If you have not set another location they can be found under HELP – SHOW ARCHIVE FOLDER.
Depending on your answers and assuming your backups did not help it may be possible to restore your data from the “.moneydancesync” folder in Dropbox.
In Moneydance 2017 click FILE – NEW – OPEN SYNCED FILE. Use the dropdown to set the same sync method as you were using. Enter the same passphrase as before and start syncing. If your data set is synced back in to your computer it will be as a second computer data set and need converting into a primary computer data set as below.
Procedure for converting a secondary data set into a primary data set.
Create a backup using the File --> Export Backup.
To use the file md2017_convert_secondary_to_master.py, first download it to your computer and then follow these steps:
1. In Moneydance, select Window --> Python Scripting.
2. In the window that opens, select 'Open Script' then navigate to the .py file wherever you saved it on your system.
3. Select 'Run' to execute the file.
4. Wait a few moments until you see a message on screen, confirming the script has run successfully.
5. Close Moneydance and then reopen it.
You should now have recovered your data set and be good to go.