@kmihaylov I use spiffs for my config file to store user preferences; thats a small json file so never any issues writing to it. I also use spiffs for html web pages, javascipt, css files etc. These are read only so I do not normally have to write to them. I remember I experimented with downloading new ones if they were available, but didnt have much luck, hangups occurred. I am guessing that size is important - have you looked at whethr larger files are more likely to cause your problems?