ESP 01 - reset settings to default values
Current ESP-01 firmware versions do not have an AT+IPR command. If you're trying to change the ESP's baud rate to use it with SoftwareSerial, the command to do so (in recent versions of the firmware) is: AT+UART=9600,8,1,0,0 for 9600 baud, 1 stop bit, no parity, no flow control.

The full syntax is: AT+UART=&lt;baudrate&gt;, &lt;databits&gt;, &lt;stopbits&gt;, &lt;parity&gt;, &lt;flow control&gt;, where &lt;databits&gt; is the number of data bits per frame, 5,6,7,or 8; &lt;stopbits&gt; is 1, 2, or 3 for 1, 1.5, or 2 stopbits (respectively); &lt;parity&gt; is 0, 1, or 2 for None, Odd, Even (respectively); and &lt;flow control&gt; is 0, 1, 2, or 3 for None, RTS, CTS, RTS and CTS (respectively). Most serial communication and devices that most of us will ever see will be 8 data bits, no parity, and 1 stop bit, abbreviated as "8N1". Flow control is sometimes used, but often it is contained in the data stream itself, such as sending Ctl-S and Ctl-Q from the keyboard to manually stop and resume incoming data transmission.