If you are receiving this error when opening Rubex: "Oops.  There was an unhandled exception, refer to the error logs for more information", this article will take you through the steps to fix this error.

Step 1:

Open your file explorer (folder icon) and type %appdata% in the top navigation bar.

Step 2:

From here click on and rename the Rubex folder to RubexOLD.   This can be done by right-clicking the Rubex Folder and selecting Rename.

Step 3:
Open the Rubex application.  It will treat Rubex like it was installed for the first time.   Select the relevant server when it gets to this screen.  This is based off of your location. 

•  Since I live in the United States I would select Option 1 to 'Connect to the US hosted Rubex (Cloud)'

This didn't resolve my problem. 
If you are still having problems with Rubex opening please contact technical support via chat at www.efilecabinet.com/technical-support or over the phone at 877-574-5505 opt3.

https://efilecabinethelp.zendesk.com/hc/en-us/articles/360041955351-FAQ-How-to-contact-eFileCabinet-Technical-Support-Help