Hi JCB
Investigations into the Something went wrong error when connecting to the STP reporting centre indicate that it is caused by out-of-date Windows versions and security certificates. To resolve that error we recommend making sure Windows and security updates are completed and that you are using a supported Windows version: System requirements
If the file is not online, you will need to put it online to set up and lodge STP Phase 2. This can also resolve that error as you're connecting to the ATO in an up-to-date browser.
Other users have reported that running the Server edition on Server 2012 R2 caused this error.
Please let me know if you need further help.
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