Message type: E = Error
Message class:  /SAPAPO/VMI_APO -  
Message number: 025
Message text: You have to specify either a GUID or number for &2
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.
Unfortunately, there isn't any extra information in this error notice.
First, use our AnswerBot below to get a possible cause and solution (requires a premium subscription).
Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.
You can also try searching the SAP support portal (support.sap.com) but you need a special user ID to access it. It is possible that an SAP support note exists that provides additional details about the mistake or even steps for fixing it.
The SAP error message /SAPAPO/VMI_APO025 typically occurs in the context of SAP Advanced Planning and Optimization (APO), particularly in the Vendor Managed Inventory (VMI) module. This error indicates that a required identifier (either a GUID or a number) has not been provided for a specific object or transaction.
Cause: The error is triggered when the system expects a unique identifier (GUID or number) for a specific operation, but it is either missing or not correctly specified. This can happen due to various reasons, such as: Missing Input: The user did not provide the necessary GUID or number in the transaction or report. Incorrect Configuration: There may be issues with the configuration of the VMI settings or master data. Data Integrity Issues: The data being processed may have inconsistencies or missing entries in the database. Custom Development: If there are custom programs or enhancements, they may not be handling the identifiers correctly.
Solution: To resolve this error, you can
 Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
/SAPAPO/VMI_APO024 Check entries for activity 'Determine VMI Purchase Order Number'
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
/SAPAPO/VMI_APO023 Purchase order number exceeds maximum length of 20 places
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
/SAPAPO/VMI_APO026 VEGRP or NRTYPE fields (or both) have to be filled
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
/SAPAPO/VMI_APO027 Initial value or entry of * not allowed in NRTYPE field
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
Click on this link to search all SAP messages.