As quite a lot of people have noticed already (e.g. here) the Synology Drive Client 3.2.0 – 13258 Update has a problem. After the update it is crashing silently all the time on my Macs. The advice from the Synology support to re-install the Drive client from scratch may be constructive but is quite tedious if you have a lot of shares configured (as for me). A hint in the above mentioned forum lead to the solution.
Obviously the password of the stored connection to the Synology NAS is corrupt after the update. Since the Drive client crashes very soon after startup the best procedure to restore the correct password is the following: