Twine win64 no longer functions: An error occurred during startup while initially synchronizing

I've been using Twine 2.1.1 just fine for a week, and then my PC happened to crash. Now, Twine will no longer function. When the program opens, it shows the following errors:

Message: Cannot set property 'id' of undefined
File: unknown
Line: unknown
Column: unknown
Stack:
TypeError: Cannot set property 'id' of undefined at IMPORT_STORY (chrome-extension://jbeclgngiacjdjjokiegbkjcpibcdcic/twine.js:40:12189) at i.(anonymous function) (chrome-extension://jbeclgngiacjdjjokiegbkjcpibcdcic/twine.js:84:5845) at r.value (chrome-extension://jbeclgngiacjdjjokiegbkjcpibcdcic/twine.js:84:4841) at dispatch (chrome-extension://jbeclgngiacjdjjokiegbkjcpibcdcic/twine.js:84:4102) at importStory (chrome-extension://jbeclgngiacjdjjokiegbkjcpibcdcic/twine.js:9:14310) at chrome-extension://jbeclgngiacjdjjokiegbkjcpibcdcic/twine.js:41:15776 at chrome-extension://jbeclgngiacjdjjokiegbkjcpibcdcic/twine.js:41:15665 at Object.loadAll (chrome-extension://jbeclgngiacjdjjokiegbkjcpibcdcic/twine.js:41:15822) at chrome-extension://jbeclgngiacjdjjokiegbkjcpibcdcic/twine.js:52:31866 at Object.init (chrome-extension://jbeclgngiacjdjjokiegbkjcpibcdcic/twine.js:53:101)

Twine will not show the Home screen, so I can't do any editing. I've tried to uninstall Twine and reinstall repeatedly, but I just always get this error.

Any help? Thanks,
--Tom