XnView Software

Hello!
I have a problem playing photocamera's .MOV files. XnView plays an audio but no video.
Installed:
Windows 7 x64, XnView 1.97.8, QickTime 7.6.9, K-Lite Codec Pack 7.1.0 .

Windows Media Player and QickTime Player play .MOV files normally.

How can I make to play files in XnView?

.MOV files are pretty generic container formats, they can have almost any form of audio and/or video formats within them. With this in mind, it's probable that your files either use an uncommon format, or one which is not officially supported in .MOV files.
Many players will ignore whether or not a given format is supposed to be within a given container and go ahead and play it so long as they have the codecs for that format. Some players on the other hand will only play back a format if it is a "legitimate" format to be within that container. I did a quick websearch on your issue & found a few posts elsewhere about people having the inverse problem (video but no audio), and their problem turned out to be an unsupported audio format, so there's a good chance your issue is simila.

As a step to solving the problem, you should open the video with an information program to see what format it's using. Mediainfo is one of the best such: http://mediainfo.sourceforge.net/en/Download/Windows

Sorry, one little remark:

On another computer with Windows XP, older versions of codecs, quicktime and XnView these files are played by XnView normally.

This is mediaInfo of such file:
Format : QuickTime
Format/Info : Original Apple specifications
File size : 12.9 MiB
Duration : 12s 0ms
Overall bit rate : 9 004 Kbps
Encoded date : UTC 2011-01-29 09:41:47
Tagged date : UTC 2011-01-29 09:41:47
Writing library : pana

Video
ID : 1
Format : JPEG
Codec ID : jpeg
Duration : 12s 0ms
Bit rate mode : Variable
Bit rate : 8 938 Kbps
Width : 640 pixels
Height : 480 pixels
Display aspect ratio : 4:3
Frame rate mode : Constant
Frame rate : 30.000 fps
Compression mode : Lossy
Bits/(Pixel*Frame) : 0.970
Stream size : 12.8 MiB (99%)
Language : English
Encoded date : UTC 2011-01-29 09:41:47
Tagged date : UTC 2011-01-29 09:41:47

Audio
ID : 2
Format : PCM
Format settings, Endianness : Little
Format settings, Sign : Unsigned
Codec ID : raw
Duration : 12s 0ms
Bit rate mode : Constant
Bit rate : 64.0 Kbps
Channel(s) : 1 channel
Sampling rate : 8 000 Hz
Bit depth : 8 bits
Stream size : 93.8 KiB (1%)
Language : English
Encoded date : UTC 2011-01-29 09:41:47
Tagged date : UTC 2011-01-29 09:41:47

The person on the other site that I mentioned also had PCM audio & that was the source of his problem, apparently PCM (or at least some form of PCM) isn't supported by MOV, so that could be causing your problem too.

It's possible that the other computer you mentioned has some different filters and/or codecs enabled/disabled in it vs your current one. If you check the k-lite settings there & make the ones on your current comp match, that might solve your problem. Other than that, a great deal of trial & error of enabling/disabling filters will probably solve your problem. The question is whether it's worth the effort.