I have errors when updating my QuickBooks from 17.1 to 2020

Please refer to the below troubleshooting steps for your problem,

Solution 1: Check the computer's system date and time

The update procedure may be hampered if your computer's system date or time is wrong.

1. To verify the computer's system date and time, do the following:
2. Right-click your desktop's system clock and choose to Adjust Date/Time.
3. Change the date and time and enter the current date and time.
4. Choose OK twice.
5. QuickBooks Desktop should be closed and reopened.
6. Return the QuickBooks Desktop update.

Solution 2: Examine your Internet Connection Settings

1. Select Internet Connection Setup from the Help menu.
2. Select When this program connects to the Internet, use my computer's Internet connection settings to establish a connection.
3. Select Next.
4. Select the Advanced Connection Settings option.
5. Select Restore Advanced Settings from the Advanced tab.
6. Click the OK button.
7. Choose Done.
8. Re-update QuickBooks Desktop

Remember the following:

• Download accelerators can stymie the downloading process. Before downloading updates, make sure your download accelerator is turned off. For further information, contact your Internet service provider.
• If you're using dial-up, make sure the minimum connection speed is 28.8 kilobits per second (Kb/s).
• If you use America On-Line (AOL), log in with the master login name if available and make sure the Parental Controls settings are not active. Visit AOL's online help for further information.