SAP MM Support Ticket raise by user:
 
We currently use MK05 to block vendors which are non approved/waiting approval from being used to buy parts from. Occasionally we give a concession to use a vendor early for a single PO, in which case we unblock the vendor, place the PO and then block the vendor again. 
 
My problem is that the MK05 and XK05 both block invoice payment so Finance have to request an unblocking each time which we would like to avoid. 
 
We do not have QM - so this is not an option at this time.
 
Solution:
 
Really quite a simple problem if you know where to look:
 
FK05 - Blocks vendor for posting/paying but allows PO's to be placed.
 
XK05 - Allows choice of blocking for both posting/paying and/or blocking PO's from being placed and lastly,
 
MK05 - Blocks Po's from being placed but allows posting and payment runs.
 

Relevant Note:
 
What is difference between deleting and blocking vendors?
 
Blocking means not allowing further supplying of materials for a particular period of time.  If you block the vendor, the master record is available in the system.  Also, you can block the vendor for a particular materials (through source list) or block centrally.
 
And you can set a Deletion flag to the vendor.  When you set the deletion flag and run archiving then the vendor master records for which deletion flag is set is completely removed from database.
 
Whereas the blocked vendor master records will not be removed even if you run archiving.
 
Deleting a vendor means you are deleting from SAP go to Tcode: XK06 and flag for deletion.
 
Blocking a vendor means temporary block for the time being you are not going to do any transaction with the vendor. You can block for several reasons
 
- You can block at company code level.
- You can block at Purchase organisation level.
 
Use Tcode: XK05 and there will several reasons for block:
- drill down from the block reasons

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