At the time of writing the current release of Syrius is 0.0.5 - if you are experiencing any issues and are not using the newest version then please try updating the wallet first.
One key change in 0.0.3 was the introduction of the embedded node (also included in subsequent versions), where Syrius syncs and runs its own node for interacting with the NoM. At first launch it will need to sync the delta or entire momentum history which can take some time (you can monitor this via the status circle on the top right of the wallet)
If problems still persist you may need to reset the Syrius cache to get it working.
- In Windows, browse to
- This is where your wallet configuration and cache files are located
- Select and delete everything except for the wallet folder and network-private-key file
- Re-launch Syrius, it will start a new sync and when completed should work correctly