The first error usually7 means there is a password on the UM area that needs to be entered before downloading but could be a memory error.
The second error also mentions memory error - not sure what this means - have never seen it before. I/O verification error possibly means that the I/O table you have in your software has been downloaded to the PLC and it is different to the actual PLC configuration. Place in program mode and create the I/O table - this may even clear some of the other errors.
Do not know about the third one.
Were you able to clear the memory error with the fourth one?
The meaning of the error codes can be found in the manual - the best place to start.
