Here Mudassar Ahmed Khan has explained with an example, how to solve the error when using DownloadString method of the .Net WebClient class along with SSL3 Security Protocol in C# and VB.Net.

Error: The client and server cannot communicate, because they do not possess a common algorithm

The above error is caused when TLS 1.2 protocol is not used before calling an API or Service and hence there is mismatch in the cryptographic algorithm.

Here Mudassar Ahmed Khan has explained with an example, how to solve the error when using DownloadString method of the .Net WebClient class in C# and VB.Net.
Error: Could not create SSL/TLS secure channel

The above error is caused when TLS 1.2 protocol is not used before calling an API or Service which uses TLS 1.2 protocol for establishing secure channel for communication.

Here Mudassar Ahmed Khan has explained with an example, how to use TLS1.2 in projects using .Net 2.0, .Net 3.0, .Net 3.5 and .Net 4.0 with C# and VB.Net.

But, the support for TLS 1.2 is available in .Net 4.5 onwards and hence this article will demonstrate how to use it in projects other Frameworks such as Net 2.0, .Net 3.0, .Net 3.5 and .Net 4.0 without upgrading them.

Here Mudassar Ahmed Khan has explained with an example, how to use the Newtonsoft.Json.JsonConvert library for Serializing and Deserializing JSON using C# and VB.Net.

The JSON string will be first downloaded from an API using WebClient class and then will be deserialized to JSON object using the Deserialize function of the JSON.Net library.

Finally, the JSON object will be again serialized to JSON string using the Serialize function of the JSON.Net library in ASP.Net using C# and VB.Net.