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It’s because the dll is targeting a different framework than what was specified in the project. Can you please try adding the reference like this?
1. Right Click on Bin folder and select Add Reference
2. Browse to the folder containing Aspose.BarCode 5.2.0 dlls
3. Select appropriate .net folder (.net framework should be same as you have specified in the project)
4. Select the dll and click OK
If you still find some problem then please share details. We’ll further investigate the issue.