Please use our Nitro cleanup utility to remove all previous traces of Nitro from your system. The utility may be downloaded from:

http://www.nitropdf.com/professional/support/resources/nitro_cleanup.zip

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 6
http://install.nitropdf.com/professional/en/retail/nitro_pdf_professional6_x64.exe

Nitro PDF Professional 6 OCR
http://install.nitropdf.com/professional/en/retail/nitro_pdf_professional6_ocr_x64.exe

Nitro PDF Professional 5
http://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:

1. In the Windows Start Menu, click Run
2. Paste the following command (without quotes) into the Run dialog:
   "start /wait msiexec /x {F0C2AD51-9F09-4B75-82EE-74DA80F708D8} EXPRESSDIR=”XX” /passive"