After the last update I no longer see any maps on the SD card. If I put them on the internal storage it works, but not when they’re on the SD card. The SD card has plenty of free space and is accessible by other apps — only VfrNav cannot access it. Because I need space on the internal storage, the SD card space is absolutely necessary. Thanks in advance.
Egon
Hello Egon,
Welcome here. 
…and as always:
→ You write that you ‘must’ offload.
That is not a future-proof concept if you have several charts and possibly approach charts, etc.
Again my note:
The information density of maps will not decrease in the future either. All of that has to be loaded from a slow SD.
Happy flying
Karstenl
So far it worked perfectly — the problem only started with the last update. It’s a Huawei P30 (Android), and the card is 64 GB, of which 12 GB are used. The Central Europe map is complete. But as I said, the SD card has been great until now.
Hello @Egon
Welcome to the forum 
It can occasionally happen that the map data on the SD card is corrupted and VFRnav can no longer read it.
Please try the following:
In VFRnav’s settings set the map storage to the SD card and close VFRnav.
Open a file manager and navigate to the path on the SD card. There should be a folder /Android/data/com.flugbetrieb.VFRnav. Delete it.
Open VFRnav and download the maps again.
Please let me know whether this worked.
Happy flying
Hermann
…in addition to Hermann’s tips ( please execute them one at a time) →
if applicable, please clear the cache of the VFRnav app.
Settings → Apps → VFRnav → Storage → Cache
…here you can also see the storage usage.
Blue skies,
Karsten
→ at this point once again and again for all readers the very clear recommendation:
After following your advice, it worked on the second try. Once again it proved: don’t give up right away. Thank you very much for the help and for the tip about the cache — I actually always clear it. You’re not at your best with a full stomach either, so I always keep an eye on it. Again, many thanks to all the helpers.
Egon
Hello Egon,
Thanks for the feedback.
One more tip for all readers:
Anyone using external SD (microSD) should spend a bit more and use industrial-standard cards! As the name suggests, these cards are tested and manufactured to industrial standards. I’ve had very good experiences with them in the Stratux context.
Especially when writing to storage, interruptions or errors can cause portions of the card to be marked… these are called bad blocks. There is only a limited space available for marking such bad blocks… just saying, in case anyone’s interested.
I like to use, for example, cards from
Kingston Industrial
…yes, they’re expensive; 8GB is enough for Stratux.
Happy flying,
Karsten
Hi Karsten,
For the Stratux I always carry a spare microSD with an identical image and configuration. That always helps to get going quickly in case of a failure and also provides redundancy. It’s usually the cheaper solution, too 
When it comes to maps on the SD that, of course, doesn’t help — in that case I’m with your solution.
Best regards
Stefan
…Great, Stefan
. That’s a highly recommendable solution!
But already since the release (…I think it was 0.29) the program is loaded into an init RAM disk (initramfs) anyway. By default nothing gets written to the card anymore, unless you explicitly enable logging. I have at least set it up that way in my image. That way you can just power it off without performing a proper shutdown.
Pilot greetings,
Karsten
Yeah — the industrial cards are just very expensive.
Hi Karsten,
You’re of course right about the RAM disk; once it’s started the SD card is no longer used. What I’m more concerned about is that the system can be ready to start again at any time, especially since we always leave the Stratux in the aircraft.
Regards
Stefan