I trust I have not missed a section of this forum on this topic but I have searched and found nothing. Following this method www (dot) ngine (dot) de / article / id / 8 ( replace dot with . and remove spaces) I have XP Pro SP3 running on a standard 4GB Kingston flash memory stick. The drivers for the computer chipset ( I got the expected messages that the USB drivers were unsigned but allowed the installation ), video and LAN port installed with no problems from CD. My requirement is to run National Instruments Measurement Studio on computers without a hard drive or Windows installation for diagnostic purposes. Normally the computers run a basic loader from either CD or a small solid state drive then the application is downloaded via LAN. I have no issue if the flash drives have limited life so long as I can recreate plus in any case I would need to build for various computer types. I have configured no paging file and best performance. My problem is that as soon as I tried to install the National Instruments application from CD after the first few steps I get an error Inset Disc 1 despite the disc being in the drive. I then tried installing the download version from another USB memory stick but this fails with an error at the same point. Also from CD I have tried installing Office XP configured to just install Word and Excel but this also fails. From the messages I am thinking either a registry error causing restrictive rights so despite being logged in as Administrator ( I have tried both the default account and an account created with Administrator rights ) some rights relating to installation are not permitted or some conflict with the Windows 3.1 installer. I don't think memory is the issue as 1GB is installed and the same National Instruments software will install and run fine on XP Embedded with 1GB RAM. Any pointers will be appreciated as now so near yet so far... Alternatively I will be grateful for any alternative methods to achieve my requirements. I have tried to post on the forum related to the method I followed but failed and noted the last post was 2009.