Message type: E = Error
Message class:  HRPAYDESV - Error Messages Germany Payroll, Social Insurance 
Message number: 666
Message text: From-date of maternity protection period must be before/same as To-date
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 HRPAYDESV666 indicates that there is an issue with the dates entered for the maternity protection period in the HR module. Specifically, the "From-date" must be earlier than or the same as the "To-date." This error typically arises when the dates are incorrectly entered in the system, leading to a logical inconsistency.
Cause: Incorrect Date Entry: The most common cause is that the "From-date" for the maternity protection period has been entered as later than the "To-date." Data Migration Issues: If data has been migrated from another system, there may be inconsistencies in the date formats or values. User Input Error: Manual entry errors can lead to incorrect date sequences.
Solution: Check Date Entries: Review the entries for the maternity protection period in the relevant infotype (usually Infotype 0060 - Maternity Protection). Ensure that the "From-date" is earlier than or equal to the "To-date." Correct the Dates: If the dates are incorrect, update them
 Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
HRPAYDESV665 Both maternity protection period fields must be filled or both empty
What causes this issue?  The <LS>Protection Period from</> and <LS>Protection Period to</> fields must be either both filled o...
HRPAYDESV664 Monthly net amount and daily net amount must both be filled or empty
What causes this issue?  The <LS>Monthly Net Remuneration</> and <LS>Daily Net Remuneration</> fields must be either both fill...
HRPAYDESV667 To-date of maternity protection period must be after/same as end date
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
HRPAYDESV668 Monthly net remuneration cannot be greater than monthly gross remuneratn
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.