How To Fix VL879 - # messages due to blocked materials regarding # materials concerned

SAP Error Message - Details

• Message type: E = Error

• Message class: VL -

• Message number: 879

• Message text: # messages due to blocked materials regarding # materials concerned

Message 'Material is blocked'
The system issues this message during collective delivery processing if
a material cannot be blocked during the creation of a delivery (SAP
block / enqueue).

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Reason
Another user or the same user who works in two sessions carries out a
business transaction (order, another collective delivery run) and blocks
this material, too.
Alternative
If parallel business transactions are also collective runs and if the
system issues this error message frequently (e.g. material M1 is in
every delivery), you cannot use parallel processing.

Error message extract from SAP system. Copyright SAP SE.