Cookie instances must be delimited by commas, here is an example: CUSTOMER=WILE_E_COYOTE, path=/, expires="Wednesday, 09-Nov-99 23:12:40 GMT"
Please see example here: PostData.
Target Platforms: .NET 9; .NET 8; .NET 7; .NET 6; .NET Framework 4.8, 4.7, 4.6, 4.5, 4.0, 3.5