Hi, it sounds like your calculator is still functioning, you may have misunderstood how to send over the OS. Here’s a tutorial for the TI 84 Plus CE: [guide|111572|stepid=213502]
Although it’s a different model, the steps are very similar. The only difference is you need to send over OS 4.2 which you can find here: https://tiplanet.org/forum/archives_voir.php?id=33155 I think your problem may have been you tried to send over the incorrect OS because I couldn’t find a compatible version for your calculator on TI’s website. Where did you happen to find your copy?
Your calculator should be working again. If it’s not, I may have something else you can try to fix it!