System.ArgumentNullException: Value cannot be null. Parameter name: key

If you receive this error message when trying to start Readysell:

System.ArgumentNullException: Value cannot be null.
Parameter name: key

This typically indicates that your local copy of Readysell has some invalid cached type data. To clear your cache, please follow these steps:

1. Right click your Readysell shortcut
2. Click Open file location
3. Find "ModelAssembly.dll"
4. Delete this file
5. Double click your Readysell shortcut again