Hi,
Not sure if this has been resolved however I too have the same issue. I have a Hikvision DS-7616NI-E2/8P NVR running firmware 3.4.80 Build 160718 however I have also tried versions 3.4.90, 3.4.91 and 3.4.92 with a recently installed Hikvision 4MP DS-2CD2345-I IP camera (in addition to 7 x 3MP DS-2CD2332 IP cams). All the 3MP cams display the thumbnails without issue during playback however the recently installed 4MP cam displays 'No Resource' when in association with the thumbnails functionality. No other issues appear to be presenting with the system and in particular with the 4MP camera. No issues with recording and playback other than the 'No Resource' message associated with the thumbnail function (Ref the pic detailing the Network Stats for the NVR).
I also noted that on firmware versions 3.4.90 and 3.4.91 the 'No Resource' message would display with the 3MP cams after approx. 2 weeks of 'uptime' with the NVR. A reboot of the NVR would correct the issue for another 2 weeks or so of uptime. I found that firmware version 3.4.80 was the 'most stable' of the more recent firmware versions for my system, certainly in relation to the thumbnail feature/function. I ran the NVR for over 6 weeks of continuous uptime and had no occurrences of the thumbnail 'No Resource' message (at least until installing the 4MP camera).
Do the 7600 Series NVR's have issues with the higher megapixel IP cameras (e.g. > 3MP???) in that there isn't sufficient CPU cycles, RAM etc. etc. or is the thumbnail feature/function somewhat buggy? I'm not particularly fussed about the thumbnails so-to-speak however I do prefer the later firmware versions (e.g. 3.4.80, 3.4.92 etc.) in relation to the playback options that provide radio buttons to select 30 mins, 1 hour, 2 hours etc. etc. for the playback footage time scale. This is purely anecdotal however the more recent firmware versions for my system 'appear' more responsive (faster) so-to-speak than the earlier versions (e.g. 3.3.4 and 3.4.0 etc. etc.). Anyway, just an observation.
Appreciate any feedback or the link (URL) to the post that covers the thumbnail no resource issue and or resolution. Thanks in advance...
Cheers!