Convert Object to byte array.

Here is my code :
Encoding enc = Encoding.ASCII;
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public void ExceptionAlerts (string lps_MessageLabel, object lpo_MessageBody) { try {
 ls_MessageBody = enc.GetString((Byte[])lpo_MessageBody);

The problem is that GetString accepts only byte[] as input, I tried to cast Object lpo_MessageBody into byte array, I get this error "Unable to convert String to Byte[]" while executing the program. lpo_MessageBody is encoded, so i used "enc" to convert it into string, where enc is an instance of Encoding. lpo_MessageBody was passed as an argument for a rule from MSMQ Trigger.

Anyone got any solution?

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