I had the same issue and just fixed it. As has been discussed here and elsewhere, dsetup.dll is now flagged as malicious. For my case, Windows Defender would delete the file if I tried to copy it to my game folder, and would delete it when I unzipped the patch files, so I couldn't even get a copy of the file.
The fix for me was to create a folder to download the patch files and make an exception in Windows Defender for that folder, as well as my game folder (I couldn't make an exception for the file, since it didn't exist...). The first exception let me unzip the patch files without issue, the second made sure I could copy it and run EQ. Someone more tech savvy than I will probably see some inefficiency here, but it works and assuming you are running Windows 10 + Defender, my guess is that it will work for you.
To create an exception in Defender go Start > Settings > Update & Security > Virus & Threat Protection. Under Virus & threat protection settings, select Manage settings, and then under Exclusions, select Add or remove exclusions.
Hope this helps.
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09-30-2019, 10:11 PM
Hybrid Mode
