Fair point, I hadn't forgotten XP Mode, but simply chose not to suggest it as a solution at this point. Not all versions of Windows 7 support XP Mode, so that isn't necessarily an option for the OP.
NI-DAQmx devices aren't supported in virtualised OSes like XP Mode, this is due to the nature of USB communication handling in virtualised OSes. Typically, they are optimised for HMI devices or Mass storage, but not higher performance devices such as USB DAQ. We don't know if the OPs application requires USB, another reason that XP Mode isn't necessarily a suitable option to suggest at this point.
Another noted issue with XP Mode is that it can brick certain USB devices for, as yet, unknown reasons. This is not limited to NI Hardware specifically, but with USB devices in general that do not fall under the HMI or MS categories and is a problem that Microsoft are actively working on. So rather than suggesting the use of XP Mode that could potentially cause problems with his hardware, if he is using any (which we don't know at this point), it is better to ask some more questions about the particular application and the OPs needs.
If the information from my last post was sufficient for the OP, then he/she needn't reply, if however, they require more information, then we can begin to explore other solutions such as XP Mode if it's appropriate.
When using older versions of LabVIEW, it is also a good idea to ascertain why/if an older version is required. It is possible to open VIs from certain older LabVIEW versions in current versions, which I'm sure you are aware, so it might be that the OP isn't aware of this and might be under the impression that he must use the same version to work with his VIs. Which isn't the case. Hence my last question regarding why LabVIEW 6.1 is required.
For the sake of the post, this information is available here. You can open LV 6.1 VIs in LV 2011.
I am completely aware that a simple search would have turned out those resources, that's exactly what I did to get the links to them. However, not all LabVIEW users are aware that there are extra sources of information available by searching ni.com in addition to the forum search, so it could be helpful to point this out just in case. Not all of the information I have sourced would necessarily be found by simply using the forum search bar, it might, but then again it might not.
Yes, I agree with you that there are other posts asking similar questions and Yes, I agree that in this instance searching for the issue at hand would probably have negated the need for this post to have been made, but whilst it is true that the OP might not have searched to see if he/she could resolve his/her issue, at least now he/she is aware of the resources that are available to him/her and can continue to be proficient and successful in the future.
hants1984: Having just read your last post, you should find the information you require in the above links. The question on LabVIEW 8.5 in Windows 7 64 bit has come up in the past a lot on these forums, the official answer is no. LabVIEW 8.5 is not supported in Win7 64, however, as discussed in the above post, XP Mode may be an appropriate solution for you.
Oli
LabVIEW Student Ambassador
National Instruments UK
