Is it possible to convert iMovie 11 library back to iMovie 10?

I have an iMovie library created with iMovie 10 on a Mac running Catalina. The library is on a portable external drive. I temporarily connected this drive to another computer, a Mac running Monterey, and I opened the library with iMovie 11. This resulted in the library being converted to a new format, which iMovie 10 cannot open.

I would like to access this library again with the original computer that can only run iMovie 10 (the latest version of iMovie that can run on Catalina, from what I gather). Is this possible? Can an iMovie 11 library be converted back to a format that iMovie 10 can access?

I considered the alternative of updating the original computer to Monterey but it's too old for this.

drusus wrote:

I have an iMovie library created with iMovie 10 on a Mac running Catalina. The library is on a portable external drive. I temporarily connected this drive to another computer, a Mac running Monterey, and I opened the library with iMovie 11. This resulted in the library being converted to a new format, which iMovie 10 cannot open.

I would like to access this library again with the original computer that can only run iMovie 10 (the latest version of iMovie that can run on Catalina, from what I gather). Is this possible? Can an iMovie 11 library be converted back to a format that iMovie 10 can access?

I considered the alternative of updating the original computer to Monterey but it's too old for this.

disclaimer: i don't use iMovie ,
But I've been doing this stuff long enough to have a pretty good idea that the answer to your problem is : you're quite likely hosed.

sometimes there could be a chance of way or hack, perhaps a 3rd party tool or similar, but almost all the time a software developer upgrades a file format or library, unless it offers the ability to down-convert within the app, there is no backwards compatibility.

this forum might not have many experts on iMovie, so perhaps look for a iMovie forum that might have more experienced users who might have a workflow workaround for you. such as https://discussions.apple.com/community/ilife/imovie

Gary3000 wrote:

drusus wrote:

I have an iMovie library created with iMovie 10 on a Mac running Catalina. The library is on a portable external drive. I temporarily connected this drive to another computer, a Mac running Monterey, and I opened the library with iMovie 11. This resulted in the library being converted to a new format, which iMovie 10 cannot open.

I would like to access this library again with the original computer that can only run iMovie 10 (the latest version of iMovie that can run on Catalina, from what I gather). Is this possible? Can an iMovie 11 library be converted back to a format that iMovie 10 can access?

I considered the alternative of updating the original computer to Monterey but it's too old for this.

disclaimer: i don't use iMovie ,
But I've been doing this stuff long enough to have a pretty good idea that the answer to your problem is : you're quite likely hosed.

sometimes there could be a chance of way or hack, perhaps a 3rd party tool or similar, but almost all the time a software developer upgrades a file format or library, unless it offers the ability to down-convert within the app, there is no backwards compatibility.

this forum might not have many experts on iMovie, so perhaps look for a iMovie forum that might have more experienced users who might have a workflow workaround for you. such as https://discussions.apple.com/community/ilife/imovie

Thank you!

drusus wrote:

I have an iMovie library created with iMovie 10 on a Mac running Catalina. The library is on a portable external drive. I temporarily connected this drive to another computer, a Mac running Monterey, and I opened the library with iMovie 11. This resulted in the library being converted to a new format, which iMovie 10 cannot open.

I would like to access this library again with the original computer that can only run iMovie 10 (the latest version of iMovie that can run on Catalina, from what I gather). Is this possible? Can an iMovie 11 library be converted back to a format that iMovie 10 can access?

I considered the alternative of updating the original computer to Monterey but it's too old for this.

Once updated, not. However, if you have an archive like Time Machine (on Mac), you may be able to recover an older archived file, not yet updated.

StoneJack wrote:

drusus wrote:

I have an iMovie library created with iMovie 10 on a Mac running Catalina. The library is on a portable external drive. I temporarily connected this drive to another computer, a Mac running Monterey, and I opened the library with iMovie 11. This resulted in the library being converted to a new format, which iMovie 10 cannot open.

I would like to access this library again with the original computer that can only run iMovie 10 (the latest version of iMovie that can run on Catalina, from what I gather). Is this possible? Can an iMovie 11 library be converted back to a format that iMovie 10 can access?

I considered the alternative of updating the original computer to Monterey but it's too old for this.

Once updated, not. However, if you have an archive like Time Machine (on Mac), you may be able to recover an older archived file, not yet updated.

Thanks. I should have a backup version still in the original format.