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How to Integrate Foreign Forms with GoSystem

This article explains how to generate XML files from K1 Aggregator for foreign forms and upload them into GoSystem using the Third-Party XML aggregation tool. This process allows you to include international tax information from K1 Aggregator in your GoSystem electronic filing submission.

Step 1: Generate the XML File in K1 Aggregator
  • Open the applicable instance in K1 Aggregator.
  • Complete all required data entry and validations.
  • Generate the XML output for the return.
  • Save the XML file to a known location on your computer.

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Tip: Generate and validate the XML file in K1 Aggregator before uploading it into GoSystem. This helps reduce validation issues during the aggregation process.

Step 2: Open the Primary Return in GoSystem Tax RS

  • Open the primary return in GoSystem Tax RS.
  • Navigate to:
    • Organizer -> E-file -> International -> Third-Party XML

GoSystem Tax RS Help and Support: https://www.thomsonreuters.com/en-us/help/gosystem-tax-rs/e-file/attachments/xml/attach-third-party-xml-files 

The attached XML file names include the locator number of the primary return

Step 3: Attach the K1 Aggregator XML File

  • Click Attach Third-Party XML File.
  • Select Add.
  • Choose Third-Party XML File.
  • Click Associate Existing.
  • Browse to the XML file generated from K1 Aggregator.
  • Select Upload.
  • Repeat these steps for each additional XML file that should be included.
  • Click Done when all files have been uploaded.
Step 4: Validate the XML Attachments
  • Review the Third-Party Attachments Summary to confirm that each XML file appears.
  • Select Validate Third-Party XML File.
  • Resolve any validation errors before creating the electronic file.
Step 5: Create and Submit the Electronic File

After all XML files have been successfully validated:

  1. Continue the normal GoSystem electronic filing process.
  2. Create the electronic file.
  3. Submit the return according to your firm's standard e-file procedures.

During the e-file creation process, GoSystem merges the attached third-party XML files into the final XML submission for the IRS.

Important

  • Only XML files should be uploaded through the Third-Party XML feature.
  • PDF attachments are not included when third-party XML files are merged. Any required PDFs must be attached separately within GoSystem.

Troubleshooting

The XML file does not upload

Verify that:

  • The file has a .xml extension.
  • The file was successfully generated from K1 Aggregator.
  • The file is not open in another application.

Validation fails

If validation reports errors:

  • Confirm the XML file was generated after all return information was finalized.
  • Regenerate the XML file in K1 Aggregator if changes were made.
  • Upload the new XML file and validate again.
  • If validation continues to fail, contact K1x Support