CauseThis is caused by files remaining from a previous installation attempt of Nitro PDF Professional that did not check if the system was 64-bit. Solution
Please use our Nitro cleanup utility to remove all previous traces of Nitro from your system. The utility may be downloaded from:
You will need to extract/unzip the files onto your hard drive before double-clicking on RUNME.bat file to start the cleanup.
Note: If you are using Windows Vista or 7, you will need to right click the RUNME.bat and select "Run as administrator".
Once the cleanup has completed, please ensure that you use the latest 64-bit editions of Nitro PDF Professional on your machine:
Nitro PDF Professional 6http://install.nitropdf.com/professional/en/retail/nitro_pdf_professional6_x64.exe
Nitro PDF Professional 6 OCRhttp://install.nitropdf.com/professional/en/retail/nitro_pdf_professional6_ocr_x64.exe
Nitro PDF Professional 5http://www.nitropdf.com/professional/builds/archive/nitro_pdf_professional5_64.exe
If the cleanup has failed, you will be given the following error: Extraction Failed. The alternative solution is as follows: