I am sorry for the inconvenience caused to you.
Could you please check and confirm the version of Lightroom you are using?
Which operating system are you using?
Please post a screenshot of the error message.
I am using a 2012 Macbook Pro with OS X 10.9.5. It has a 2.6 GHz Intel Core i7, 8 GB 1600 MHz DDR3, NVIDIA GeForce GT 650M 1024 MB and has been running LR5 with no problems. I used my new subscription on my brand new Macbook air with upgraded RAM and processor. With that I had a major import problem (ie wouldn't import) until Adobe released a fix. Now the import and conversion is still painfully slow and at best I would say LR6 is 'buggy' on each machine. Everything takes forever and is really 'jerky' and delayed.
My latest problem had to do with the conversion of one of my LR catalogs. The new version wouldn't load most of the thumbnails - I just reverted back to using the old version of the catalog since the updated catalog isn't working.
I hope Adobe will try a bit harder to get it right next time before releasing a new version. LR5 worked perfectly! What is the thinking behind replacing something people are happy with to something that doesn't work nearly as well?
I don't think Lightroom CC is a disaster; I have subscribed for several years without a hitch, as have many people in this forum. Rather than "...hope Adobe will try harder..." your time and that of other users on this forum, would be better spent trying to solve your particular problems.
In your first post, you indicated that you "...decided a couple months ago to switch to the CC version...", but in your last post above, you are referring to LR6. For clarity, which version (exactly) of LR is giving you a problem as already asked by Mrinmay Majhi above? We cannot help you if you do not provide us with the information requested.
One thing you can try that has cause slowness on some computers in both LR CC and LR6 is to turn off "Use Graphics Processor" found in Lightroom Preferences under the Performance tab. Let us know if that helps.
jwilliams, make sure you are NOT running 2015.2 or 2015.2.1. Those versions were extremely buggy, especially on Mac OS X. You should be running 2015.1.1 or 2015.3. Also, as Joe says, it is essential to turn off graphics acceleration as it slows down Lightroom terribly if you don't have the very last hardware or if you use any brushes in your editing. The other thing to be mindful of is the face recognition. This will bring Lightroom to its knees if it is trying to find faces on everything. Make sure to turn off the automatic face recognition on import and to not have it running in the background.
Jao vdL - Thanks! That was helpful and it seems to be running better. I appreciate your time!
Thanks for your reply. I am running the latest CC version though when it loads or creates catalogs it is saying it has to update the older versions to LR 6. I have turned off the Graphics Processor and made sure some of the other background features I don't use are turned off. It still runs slower than my version of LR 5 but is doable. I am finding the Import feature is where it is especially slow.