As the other thread is quite large and not a lot of info about Service des automobiles et de la navigation Lausanne and I think that this is a quite different story of what I read before.
In July I applied to have my license converted. Did everything, I got my temporary license valid until November. In September I received a date with 9 days to spare. I had arranged classes with an instructor before even it was a bit of a stretch, I didn't complain. One day before the exam while running I had pain in my back. I called to cancel my appointment for the next day and I went to my doctor for a visit. I had small injury recently and had been visiting him for the last 4 months for the same issue. He took me (on the day of the test, which I canceled) had what I needed for my back and gave me a medical certificate specifically written for the SAN stating that I visited him on this date for back problems.
I took this certificate couple of days later to the SAN and they said, no problem we will send you another appointment by mail next week. 3 weeks later I receive a registered letter with all my documents, my old licensed (annulled) and a fine for not presenting to the appointment, automatically forbidden to drive in Switzerland. That can't be right, first I canceled my appointment second I took them a medical certificate. My driving instructor was involved all the time and he was furious of what kind of bull they were doing to me. He went there couple of times, first they refused to give a reason for this decision and after 2 weeks they confirmed that it was a mistake on their part and that they will send me my appointment. 3 weeks later waiting I receive a letter from the lawyer of SAN Lausanne, stating that, as my medical certificate is NOT VALID, he will not give me another appointment for a driving test and he reminds me that I don't have the right to drive in Switzerland.
My driving instructor went there to see this lawyer but he was refused a visit, it was not possible to talk with this guy. I went there next day (my french is limited) and I demanded to speak with somebody who speaks Italian. I requested to see the lawyer and ti give me a reason WHY my medical certificate is not valid, but also the same answer, not possible to meet him. After refusing to leave until I was given a reason for the validity of the certificate, they told me that the certificate did not include details of my sickness and it was not well written that I was not able to drive on that day.
I went to my doctor explaining this and he is shocked, because to disclose personal details on a medical condition is ILLEGAL. He gave me his phone details and said just give this to whoever wants to talk to me and demand that details from me and I will set them straight. Going back to the SAN, they refused to call my doctor but rather he calls them and specifically the doctor that works for SAN who comes to work only 1 day per week. OK, I am bothering my doctor but he is willing to help, after 2 unsuccessful weeks of calling the SAN he finally got a hold of their doctor. After showing bills going back to 4 months before my test and stating from my doctor that he received me on that date with back problems and treated me, they requested a new medical certificate where he will write that I was not able to drive on that day.
They could have requested this the very first day they saw my certificate and not take me into a maze of 4 months constant phone calls and bothering
- my driving instructor
- people at the counters that had no idea why is this happening to me
- the Spanish lady at the Measures Administratif that was going back and forth to the lawyer's office to bring messages from me
- my doctor
After all was clear, I receive my new appointment, this time 6 days in advance.

I took 2 days of lessons and I went in today, passed it. What a huge relief. 4 months of phone calls, problems and not being able to drive.
The test itself was not that hard but it was crucial to have a bit of lessons with a driving instructor. And the controllers seem to be more comfortable when you come with a driving instructor and you take their car for the test.
Sorry, it was a long read!