When an Inno Setup-based installer fails with a message mentioning isdone.dll , the actual underlying problems are typically:
: Installations downloaded from unstable networks may have damaged archives that the library cannot process. Security Interference
If you are certain the file is missing, you can find a replacement on DLL-files.com . Download the 64-bit version of isdone.dll . Paste the file into C:\Windows\System32 .
Not enough virtual memory on your hard drive.