Charles, Thanks for the reply, No I have not as I have never used the commands for HSEROUT or HSERIN to do my serial activities. I ahve always used interrupts. I used to use an old set of interrupt routines originally written by Tim Box but for the last few years I have used the DT_INT routines as they seem more stable. I have as a few of the first lines in my interrupt routine a check for the overflow bit being set. There is no interrupt for the overflow bit being set. It is up to the operator to check this bit and clear it if it is set. If it IS set there will still be an interrupt generated for the RXREG having data in it. If it IS set then after reading the data in the buffer and NOT resetting it you will NOT receive any more data into the RX shift register. The problem I am having is that ALL interrupts are comming to a halt if there is an over run. It doesn't matter which USART you are using. I have the same code working on an 18F2620 with out the second USART and have NEVER had this problem.