KING ERP error message "Unexpected character encountered while parsing value"

Check the following in the relevant administration:

It is possible that this needs to be restored. Entering a 5-digit starting number in the field 'sequence number' (for example 00001) usually resolves this. See image:

The message 'Index 'Idx_DarNummer' for table 'tabDigitaalArchief' would not be unique' is also related to this.

If this is not the solution, perform a test booking with a document < 20 KB and check the error message again. This will give you insight into what still needs to be adjusted in KING ERP.