Replied 8 September 2017, 12:33 pm EST
This error message suggests that you have the SerializeModels property of the SheetView set to True and in this serialized data is some version number being stored. The error is either coming due to not having the resx file attached with the project or not having the version of Spread that is being referenced correctly loading the information from the models.
If the first issue is your problem, you just need to move the resx file into the project and reload. If the second issue is the problem, you either need to reload the older version of the project that did load and set the SerializeModels property to False and resave the project for loading into the new version. Or, set up a binding redirect for your project or framework to load the correct version of the assembly. You can find steps to implement this in our readme under the upgrading project section.