image uploading problem

This is the message I get when uploading images to media:
� %�1O�0�w���;q�ly� ���
ft�����|���������N=tד�zx5�>�/� �<��E��twrlZ)���j��k5��j� ��m����= %w�nq*��7X�PI�!#�”�����H��/�{�w�F�W�?+f�i��b]`6T>ſ�nA� �Mvt\D�Xk������*Q�]5�%Ӷq_Wgm���U{
Verarbeiten …
¬� %�1O�0�w���;q�ly� ���ft�����|���������N=tד�zx5�>�/� �<��E��twrlZ)���j��k5��j� ��m����= %w�nq*��7X�PI�!#�”�����H��/�{�w�F�W�?+f�i��b]`6T>ſ�nA� �Mvt\D�Xk������*Q�]5�%Ӷq_Wgm���U{
Verarbeiten …
¬� %�1O�0�w���;q�ly� ���ft�����|���������N=tד�zx5�>�/� �<��E��twrlZ)���j��k5��j� ��m����= %w�nq*��7X�PI�!#�”�����H��/�{�w�F�W�?+f�i��b]`6T>ſ�nA� �Mvt\D�Xk������*Q�]5�%Ӷq_Wgm���U{
Verarbeiten …
What can that signify? No traces in the uploads on FTP.
Thanks for an explanation. All usual suspects have been checked.
Hans