Hello many thanks for your reply.., what information do you need..?

Click on my blue text and follow it up

Apple Macbook Pro 2019 Mac OS Big Sur - AMD Radeon Pro 5500M 8 GB - 2.3 GHz 8-Core Intel Core i9 - 64 GB 2667 MHz DDR4
- Parallels 17 - Windows 10 Home 64 bit Vegas 19 Pro. These files have played previously on this set up, I am now wondering if by upgrading to Windows 10 from Windows 7 has created my problem.., I still have Windows 7 and Vegas 16 running on another recent Macbook Pro through Parallels 17 and the same file are still usable.

This is no MediaInfo as asked in that link I send you

Sorry i'm new to this.., I don't understand what you are asking for..?

I'm using the latest build of Vegas 19 (361 or 381).., recently downloaded from Magix.

That trouble file is packet in a so called "mov"- wrapper.
In that wrapper are all kind of codecs possible and Vegas maybe cannot edit the one that gives you trouble.
To see which codec was used I asked you to use the free app MediaInfo to give all that needed information. I did send you the link to a page on this forum made by Nick Hope, where you exactly can read how to manage that MediaInfo.
In blue on this forum are links and by clicking on that blue you are redirected to the right place.

Thank you for the information you have given me, I shall have a look at your recommendation.., it is very much appreciated. I ran one of the clips i'm having trouble with through a demo file conversion program (Movavi) earlier setting the output file as also .MOV keeping the file size the same and Vegas excepted the file again in the timeline with (I hope) no degradation in quality. I will look at MediaInfo to gain more knowledge on this subject and to understand your advice. Thank you so much for your time on my behalf.

Thanks for your anecdotes. Eric is asking for your File Properties. To give us your File Properties, he is asking to download and use a free utility called MEDIAINFO.

To make it simpler for you, here is the specific section for downloading and using MEDIAINFO ro report your FIle Properties. We certainly hope this is clear to you; it is actually pretty straightforward:

https://www.vegascreativesoftware.info/us/forum/faq-how-to-post-mediainfo-and-vegas-pro-file-properties--104561/

Hello I am having a problem loading some .MOV files (but not all), through enabling Quicktime plug-in I can view some .MOV files but not others.., i've tried some codec packs including installing Apple Quicktime with depreciating features ticked but no luck., is there any codecs I can use to sort this..? Previously all .MOV files would play but now not files I purchased at Shutterstock.., these files now show in Vegas as blue thumbnails with a clapperboard in the middle.., I can not use these in the timeline. I don't want to change the files to MP4 files because I think some detail and clarity in the file is lost through compression., do they have to be compressed..? Thanks in advance, any help is greatly appreciated.

I had simialr problem where some QuickTime files open and others did not. But after installing QuickTime player and Avid DNxHD codec I am now able to open all MOV files.

Hello I am having a problem loading some .MOV files (but not all), through enabling Quicktime plug-in I can view some .MOV files but not others.., i've tried some codec packs including installing Apple Quicktime with depreciating features ticked but no luck., is there any codecs I can use to sort this..? Previously all .MOV files would play but now not files I purchased at Shutterstock.., these files now show in Vegas as blue thumbnails with a clapperboard in the middle.., I can not use these in the timeline. I don't want to change the files to MP4 files because I think some detail and clarity in the file is lost through compression., do they have to be compressed..? Thanks in advance, any help is greatly appreciated.

I had simialr problem where some QuickTime files open and others did not. But after installing QuickTime player and Avid DNxHD codec I am now able to open all MOV files.

Thanks for your information I shall keep that in mind. I have since cured my problem.., I put my troublesome .MOV files into Movavi Video Convertor and converted the clips into .MOV files again keeping the file sizes the same as the originals with no compression and it's worked a treat., all good with no degradation of video quality.

@Graeme-Pratt  Good to know you solved the problem.

Is Movavi Video Convertor the best tool when it comes to video converstions?

@Graeme-Pratt  Good to know you solved the problem.

Is Movavi Video Convertor the best tool when it comes to video converstions?

It seems a good conversion program, there are many options.., I like the option to select the compression size so I can keep my files the same size as the originals.

WIll give it a try. Thanks.

Hello I am having a problem loading some .MOV files (but not all), through enabling Quicktime plug-in I can view some .MOV files but not others.., i've tried some codec packs including installing Apple Quicktime with depreciating features ticked but no luck., is there any codecs I can use to sort this..? Previously all .MOV files would play but now not files I purchased at Shutterstock.., these files now show in Vegas as blue thumbnails with a clapperboard in the middle.., I can not use these in the timeline. I don't want to change the files to MP4 files because I think some detail and clarity in the file is lost through compression., do they have to be compressed..? Thanks in advance, any help is greatly appreciated.

It seems installing codec packs is useless. Maybe you can try a different video player like VLC to play MOV files to see if it works?

Converting MOV to MP4 is an ideal way, as there are many advantages:

1. MP4 has better compatibility than MOV: MP4 is internationally recognized and used as the most popular video format for iPhone, Android, tablet, PC, operating system, and media players, while MOV is mostly intended for Apple’s devices and software, popular drones, and cameras.
2. MP4 format has smaller file size: MP4 files are relatively more compressed than MOV.
3. MOV files often encounter errors like can't play, can't edit, and can't upload, to name a few.

It depends on you. There are many MOV to MP4 converters including software and online if you need a conversion one day.

@wood-a

Your response is a little confusing, as well as coming 4 months and 19 days after the OP's last response, before he apparently dropped out of his discussion topic.

FYI, the MOV and MP4 containers are 100% compatible and 99,9% interchangeable; it is the encoding format and the Vegas decoder in use that are in question here, and only those.

Here is some basic vocabulary to help you begin to understand the differences between container rewrapping and format conversion. In the meantime, please thoroughly research any advice you feel compelled to share, thanks.

https://www.vegascreativesoftware.info/us/forum/speaking-good-video-a-beginner-s-guide--104463/

Among the Pro users here Handbrake is the usual recommendation for converting to a mp4 file which Vegas will happily handle, and without any noticeable quality loss.

@Musicvid

Thanks for your suggestion.

Hi. I'm having the same problem except with files that are already mp4's. After using hundreds of these with no problem, they started giving me trouble (even super short clips like the 4 second one below) and I would usually just delete them and redownload them from Google photos (sometimes it would take a couple times) but I could eventually get them to work — even if restarting Vegas or my system. When importing into project media, the actual thumbnail appears for a split second but then turns blue and cannot be dragged onto timeline. I feel like I should be able to figure this out from what's already been said here but want to be sure as this is happening near the close of a massive, months long project. Appreciate help.

@skrootayp
Which program with buildnumber are you using?

Vegas Pro 16, build 424

Sorry, I cannot help you