QuickBooks Error code 1603 happens when QuickBooks requires some components to run, but these components are not available. 

Some of the reasons for occurrence of this error are:

• Microsoft .NET framework might be having some issues. 
• Some windows issues may cause this error. 

Error 1603 can be fixed by: 

Repairing the Microsoft .NET framework.

•  From programs and features, turn windows features on or off and uncheck .NET framework. 
• Reboot the system and again check mark the .NET framework. 

Hopefully, this error is now fixed. If you still face any issues regarding any error, you can reach out to QBSsolved at +1(888) 910 1619.