I just received a fax on my mp530 and it said received in memory. How do I print it out?

SOURCE: printing what is in memory

It probally wants ink to print the stuff in memory, if this has been corrected you can make it print from its memory or you can delete each file, it takes a little doing but this is what you need I think to do so you can free up the memory, to delete a item from memory, press menu, then scroll to a memory item, ok , scroll to delete, ok to delete, ok to delete, menu to get out quickly, standing on one leg :-)

You should be aware that this printer has a serious "ink low" behavior. When any ink cartridge is getting low (which still means a lot of ink left by the way), it changes the Fax reception model. Instead of printing your faxes as they arrive, it dumps them into memory. So, even though yellow (say) is low, it will not print your B&W fax!
It takes more than 5 steps to print the fax and delete it (menu, scroll to memory item, ok, scroll to print, OK document, scroll to print all pages, ok, menu to go up, scroll to delete, ok to delete, ok to delete, menu to get out).
Worse, after a couple of these, the memory is mixed up. So, when you want to send a Fax, it will say "memory full" even though the memory is empty. You then have to power cycle the printer (hold down on/off for 1 second, wait 10 seconds, power on, wait for it to get ready (another 10-20 seconds).
This means you either have to waste ink by throwing out cartridges before they are empty, or you have to deal with this mess.

SOURCE: There's a fax in the memory - I can't print it

if there is a fax in the memory press memory reference, scroll down to 'print all in memory'

SOURCE: Memory full

check the manual, you can bypass the memory by printing direct, or just print everything in memory hre is the link
http://www.retrevo.com/

SOURCE: Canon MP530 receive fax issues

Receive Mode Settings Select from the following receive mode options to suit your needs. Once you've decided on which receive mode to use, follow the below instructions to set the receive mode using the operation panel. Receive Mode Setting

1. Press the <FAX> button to enter Fax mode.
   
2. Press <Menu>.
   
3. Press the right or left arrow button to select [Receive mode settings], then press the <OK> button.
   
4. Press the up or down arrow to select the receive mode that best suits your needs, then press <OK>.
   
   

Types of receive mode
Select the receive mode according to your needs.
Receive mode
Purpose
FAX/TEL AUTO SW When you want to receive faxes automatically as well as voice calls. FAX ONLY MODE When you want to receive only faxes automatically with your machine, or have a dedicated telephone line for FAX use only. DRPD When you have subscribed to a DRPD service with your telephone company. MANUAL MODE When you receive mainly voice calls and sometimes faxes, or want to receive faxes manually. ANS.MACHINE MODE When you want to receive voice messages on your answering machine and receive faxes automatically. FAX/TEL auto switch
FAX :
The machine does not ring but will receive the fax automatically. Voice call :
The phone attached to the machine will ring. Pick up the handset to answer the call. Note:

• Ring start timing and Telephone ring length can be specified in FAX/TEL auto switch in the Receive mode settings.
  
• If you want the telephone to ring when it receives a fax, connect a telephone to your machine and enable the Incoming ring settings in RX settings.
  
• The phone attached to the machine may not ring depending on the telephone type you are using.

FAX only
FAX * :
The telephone does not ring. The machine will receive the fax automatically. Voice call :
You will not be able to answer the call. * If you want the telephone to ring, connect the telephone to your machine and enable the Incoming ring settings in RX settings menu.


DRPD
FAX :
Your telephone line will ring according to the ring pattern you have chosen and receive the fax automatically. Voice call :
Your telephone line will ring according to the ring pattern you have chosen. Pick up the handset to answer the call. Note: Specify the FAX pattern in the DRPD: Set FAX ring pat. in RX settings menu.

Manual RX
FAX :
The telephone attached to the machine will ring. Pick up the handset and if you hear a beep tone, press the <Color> or <Black> button on the machine to receive the fax. Voice call :
The telephone attached to the machine will ring. Pick up the handset to answer the call. Note: If you are far from your machine, you can use the remote receiving function to receive faxes. Pick up the handset of the telephone connected to the machine and press 25 (the remote receiving ID).

Ans. machine connect
FAX :
First the answering machine connected to your machine will respond to an incoming call, and then the machine will receive faxes automatically. Voice call :
The answering machine connected to your machine will respond to an incoming call. Note:

• Set the answering machine to answer on the first or second ring.
  
• The entire message should be no longer than 15
  

SOURCE: Canon MP530 - Fax Memory is Full... How do I clear?

Solutions 3 and 4 are basically correct, they just leave out a few steps:
1. Press FAX button
2. Press buttons in following order:
Menu, + (right arrow), OK, +, +, +.
You should see Delete Document. If not, press + or - (right or left arrows) until you do.
3. It will show a document number, like 5004.
Press OK
4. It will show Yes No. Press - (left arrow) to select Yes.
5. Press OK
Note: Steps 3 and 4 may be reversed on some similar models.