Below is my original question that I posted.

Things have moved on a little since then.

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Unable to open excel files on new laptop

Background.

Excel files created with office 2013, On original machine.(Windows 7 64 bit)

Files copied over to new machine.(Windows 8.1 64 bit)

2 types of file extension........ xlsx And xlsm.

On new machine I am running office 365.

Standard files with xlsx extension can be opened on new machine....... no problem.

Files with xlsm extension (macro enabled)Will not open and the following message is displayed.....

" Excel cannot open the file............Because the file format or file extension is not valid.

Verify that the file has not been corrupted and that the file extension matches the format of the file"

Could anyone explain how I can get round this problem.

I do not wish to make any changes to the macro enabled files.

They were written for me and as I am only just starting to get to grips with VBA, I do not have the knowledge.

Regards     Alan

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Have now worked out how to get xlsm files to display on new machine.

Have copied over and opened a personal.xlsb file which contains the macros that my xlsm files use.

These files now open on new machine, but I appear to have run into another problem....... as follows

All my colour formatting has disappeared. Purely displays black-and-white.

Font settings have changed.

Column width settings have changed but not back to basic same width all columns.

Strangely, some columns contain  simple formulas and these have not disappeared.

Have attached simple old / new images as illustration.

Realise that I am totally out of my depth on this one. Suggestions gratefully received.

Regards      Alan

Edit.

Cannot upload image.

Account verification ?

Hi Alan,

Based on your description, at first you copied the .xlsm file from old computer to new computer but you can't open it. Then you solved this issue by copying personal.xlsb to the new computer too. Now you got the new issue, your files opened without formatting.

Could you tell me if this issue also appeared in the .xlsm file or all files? Have you ever tried to create a new file and check if it works fine?

If you have no verified to post the screenshot, I suggest you upload the screenshot via OneDrive.

Or you could send this screenshot to our email address:

ibsofc@microsoft.com I'd like to help you check it.

Please Note: The email subject you should use the URL or the Title Name of your case.

I'm glad to help and solve your issue.

Regards,

Emi Zhang
TechNet Community Su

Thank you so much for coming straight back with offers of assistance.

I was about to start creating and testing new files as you suggested.

However, as I started to setup and make more  use of my new laptop, I noticed that my browser display for websites was showing a distinctly stripped out colour look. (Background colour formatting etc not displaying )

I then went back to my Excel files and although visually there is no colour formatting,  this time I actually opened the cell formatting and discovered that all my settings are correctly there.

I now believe I have some kind of display problem.

New laptop is HD 2560 x 1440 And running Windows 8.1 which I am not familiar with.

Either one, or a combination, is almost certainly causing my problem.

I do apologise for wasting your time over this matter.

Thanks     Alan

PS   anyone recommend a good forum where I can begin my new problem search.