Solution : https://service.sap.com/sap/support/notes/503422 (SAP Service marketplace login required)
Key words :
dummy=dummy&mig=2194687612341234works correctly, dummy=dummythese dummy parameters, mig=2194687612341234to prevent, personalized e-mail, terms crm marketing, e-mail reason, url partly consists, dummy=dummy, &mig=2194687612341234that, entire url
Related Notes :
| 501533 | CRMD_EMAIL: incorrect or empty correspondence in activity |
| 454456 | CRMD_EMAIL:Performance improvement during mail text creation |