Internal sync error . Please try again later.

If you haven't done so already, please try the following actions:

• Even if you are on the latest software level already, download and install the latest Mondo Patch file from https://www.quicken.com/support/update-and-mondo-patch-20182019-release-quicken-windows-subscription-product to ensure your Quicken software is up to date and correctly installed.
• Reboot Windows.
• Validate and Supervalidate your Quicken data file.
• If nothing helps, try to restore your Quicken data file from an Automatic or Manual backup taken just prior to the problems first occurring. https://www.quicken.com/support/how-backup-or-restore-your-quicken-data

Validate and Supervalidate instructions

First save a backup file prior to performing these steps

Validate: 

1. File
2. Validate and Repair File...
3. Validate File
4. If the data file contains investment accounts also select "Rebuild investing lots". If you suspect that a damaged Quotes Price History causes your problems, also select "Correct investing price history" functions "Delete" or "Repair and Rebuild".
5. Click OK
6. Close the Data Log
7. Close Quicken (leave it closed for about 30 secs)
8. Reopen Quicken and see if the issue persists.

Super Validate:

1. File
2. Press and hold CTRL + Shift while you click Validate and Repair File...
3. Supervalidate File
4. Click OK
5. Close the Data Log
6. Close Quicken (leave it closed for about 30 secs)
7. Reopen Quicken and see if the issue persists.