Thanks all for your suggestions! Alexander's suggestion worked! Installing the newest software versions solved the Problem for me! GPG 2.2.7 libgpg-error 1.31 libgcrypt 1.82 libassuan 2.51 libksba 1.35 npth 1.5 -- Jonas Hegemann Technische Universitaet Dortmund Lehrstuhl fuer Theoretische Physik I D-44221 Dortmund, Germany