I run Rocksim using Windows 10, and my hard drive died last week (also the back-up drive had failed also). After having a SSD install, and reloading what info was salvageable off the original hard drive,I started getting an "Access Denied" message when trying to save a modified or new Rocksim file (also had the same issues with other files). Now I'm not a computer geek, so after a couple days of heartburn messing with this issue , I contacted Apogee. They said this was only the second time they had heard of this issue, but contacted the developer of the Rocksim program. He said that Microsoft has changed the permissions on the Program Files (x86) folder, and now programs are not allowed to write data to these folders. He does have a fix in the works, but the simplest work around is to move Rocksim out of the Program Files (x86) to a different folder. After doing this, everything seems to be working correctly. I hope this information can help others if they run into the same situation.