1) Make sure you're on the latest release https://github.com/syscoin/blockmarket-desktop-public/releases/

2) Try shutting it down and waiting a full minute before starting up again. 

In most cases, this solves the issue. 


If this does not solve the issue then:

1) Close the wallet
2) Find your Data Folder:

The Data Folder on Windows is C:\Users\[USERNAME]\AppData\Roaming\Syscoin

The Data Folder on Mac is /Users/[USERNAME]/Library/Application Support/Syscoin

Rename the Data Folder: Sycoin-Old 

(This step simply moves the files. This will be your backup)

3) Create a new, empty folder called: Syscoin

4) Copy wallet.dat from the Syscoin-Old folder to the new Syscoin folder.

5) Restart the wallet and wait for it to sync up again.

There is a green bar on the Overview page that indicates syncing progress.