Qirehtox

Every time I attempt to export a movie, after finding the file location I wanna save it on and clicking 'save' on my Windows 10, this pop-up opens. It's not to do with video length because I've saved longer movies with ease, and the only render options I've touched are the Width & Height of the camera size as well as the Tempo in 'Project'. I've tried saving another movie I've made and that worked, as well as freeing up some computer storage and nay to that as well. This video is kinda important and I really wanna get it out as soon as possible, and any help is so much as worth money for all I care.