QB Issue Resolution:
Once the Multi-Currency already set-up, it can no longer be switched to a different currency. The only option I can think is to restore the backup of the file (without the currency set-up) and choose Euro on the restored backup as the home currency.
Hope this helps.
Resolution for Issue 'I have recently set up a new company on quickbooks 2014 and the currency defaulted to GBP, can I change it to Euro?' available: Yes (Solved).
Source: Intuit Community forum.
I have recently set up a new company on quickbooks 2014 and the currency defaulted to GBP, can I change it to Euro?: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.Support for Quickbooks
Quickbooks Repair Pro will resolve it efficiently and affordably. Guaranteed resolution of your issue, or you pay nothing!
Error Recovery for Quickbooks [Canada]
E-Tech is the #1 Quickbooks data migration and Conversion service provider.
Additional Support Options: