I was running a program on my Windows 10 computer Build 1709 that was located on my Windows 2003 server. The executable was located on the server. I upgraded to 1803 and it no longer works. A second computer did the same thing and I was able to go back to build 1709 and it started working again. I can't go back on the computer that still has 1803 because it's been more than 10 days or 7 or whatever. Research was pointing to the probability it was an SMB share issue. I saw that supposedly 1803 does not support SMBV1 which is what Server 2003 is using. However, I go into the Windows features settings and is shows SMBv1 checked off. When I run -get smbconfiguration or whatever in powershell it returns the version as 1.5. Anyway, I also saw some suggest to install AVG or Avast which disables Defender. I've done that and did not work. I've tried running it in compatibility mode and that didn't work. Looking for suggestions. If it is an SMB issue, there is no way we are upgrading the server at this time. I can resinstall Windows on the workstation if I have to, but I would love to avoid it enough that I joined this site and posted for the first time hoping someone can offer another suggestion. Thanks.