I guess the question is, how can the sample memory be full with only 275MB?
The answer could be that you exceeded the memory by having more than 1GB of data, by having more than the total number of allowable Waveforms, or by having more than the total number of allowable Samples.

It is a “whichever comes first” thing. If you you exceed the maximum number of Waveforms, even if you have not filled the 1GB, you are out of memory. If you exceed the maximum number of Samples, before reaching the maximum Waveform or maximum total memory, you will be out of memory. Whichever Limit is reached first.

It’s 275MB but how many Waveforms, how many Sample Keybanks?
What else do you have in memory at the time?
And exactly how and where are you Loading the File. For example, loading using the Import Option = Voice should allow you accomplish your goal. (Depending on how you created your MOXF Performances... you may wind up duplicating data).

Suggestion:
Save your current User Bank to a File (if you have not done so).
Place your MOXF ALL data file .X6A on a thumb drive
Press [UTILITY] > “Contents” > “Load” > set the “Contents Type” = User File
This will overwrite your current User Bank.
Select “Import Option” = Voice
This will load all 384 MOXF User Voices as Single Part MODX Performances, all the Waveforms, and User Arpeggios that make them work.

Let us know if you are successful loading Voices in this fashion.

Thank you for your input.
I removed the 1gGb Flash board from the MOXF. (The .wav files on this board were mostly sound effects, but it was almost full)
So that solved the problem with too much memory.
However
After removing Flash I went through all my MOXF Performances (about 40) to make sure they were intact. They are only patches with four tweaked Voices and some splits and octaves. No songs or arpeggios. (of course the named Performances that only contained .wav sound effects have no sound now)

Saved this to a fresh USB using SAVE ALL With Sample.
Loaded it as you Exactly as you instructed to the MODX.

Very weird. Only about 3 or 4 of the MOXF Performances show up by Name; and they are single voiced and not split; About 36 out of the 40 are simply not there by name and I don't believe they are there and not named.
Most of my named "Performances" that contained only sound effects form the FLASH DO show up as a Named Performance on the MODX; But of course there is no sound in them.

That's news at 11. Thanks again.

And then I did these same steps but loaded it to PERFORMANCE and voila Most of my User Performances with splits and four voices show up as named on the MOXF.
Not exactly, but good enough to save me a lot of work re-creating them.
So I'm good for now.
Bad Mister, thank you for all your input, not only to me but all the thousands of folks you've helped over the years.
You must have the patience of Job .......!!