i deleted my gmapprom.img file

If using Windows open up Windows Explorer, right click on the Nuvi drive, then select properties.
This will indicate how much space is available.

Now look at your Gmapprom backup and see the size.
If less than space available then it should fit.
Also DO NOT cut and paste the backup file, COPY the backup gmapprom.img file.
Only copy back the gmapprom.img, nothing else.

If not enough space, delete most of the voice files you do not use to free up some space.

First - good for you for backing up your nuvi.

Are you using a PC or a Mac?

Next, what you are saying does not seem possible. If you accidentally deleted the gmapprom.img file, then that same amount of space should be free on the nuvi.

Could you have renamed the file? or moved it into one of the folders on the nuvi?

DO NOT do any "cut and paste" (although you are probably just using those words as a figure of speech). There is danger in "cut and paste". As mentioned above, COPY!!!

Do not do anything too fast. Figure out what you did and then see what you can do to reverse it.

I use Cut and Paste all the time. What is the problem with using cut and past. I use it to make a back-up of my nuvis.

Based on an experience I had with my first Nuvi 660 it is possible the ram became corrupt. I had deleted some files but apparently they remained on the unit and showed less free space available. I spent hours on the phone with Garmin support but unable to correct.
My last resort was to run chkdsk on the Nuvi but Garmin support suggested I don't do it.
I took a gamble and did it, it found several errors and fixed them and I regained all my lost space.

I don't suggest anyone try it since Garmin did not approve using chkdsk, I just thought I'd mention the fact there is a remote possibility that the ram is corrupt.

By using CUT, sometimes it will do just that, it removes the file and pastes it to a new location.
By using Copy, it copies the file and leaves the original in its place.

I find when using cut, if you are pasting on the same drive the original is moved. But when using cut and paste to another drive, the original remains.
But I have had this fail at times and the original did move to the other drive.

Always safer to use copy, once transferred easy enough to delete the file from the original location.

In my experience just the directory entries changed to show the the revised location but the file itself never moved.

Some apps and OS's use the term 'Cut' and 'Paste', but under the hood it it just a copy. To be perfectly safe, highlight the file, do a Cntl-C, go to the Garmin directory and do a Cntl-V. NEVER do a CNTL-X.

(in Windows OS) It is a BIG problem if your intention is to back up. The original files will be gone after pasting them to the destination folder. You should be doing COPY instead.

That's incorrect. (Assuming Windows OS) Cut and paste will always delete the source files regardless of the drive (or partition) location. What you describe sounds like a drag and drop behavior. If you drag and drop within the same drive (or partition) the source files are deleted (or moved to the destination). However, if you drag and drop between 2 different drives (or partitions, eg: drag/drop from C to D), the source files remain intact.

@chewbacca
You are correct.
I always use the drag & drop method, not cut & paste.
Highlighting file or folder then pressing the ctrl key copies the file or folder to the selected destination. Using the shift key moves it.

I find it faster doing it this way and have been doing it instinctively for years.

I use copy and paste not cut and paste.

I need link to get back gmapprom to my garmin 255w wich by accident i have deleted.Please someone help if possible?!

You can use Garmin's map update software to reinstall your map. That's the easiest way to get the map file restored. Use either Garmin Express or GarminMapUpdater.