.xls Extension needed in Filename

[Westicle]

Some of my macros that have been running fine for the last few months have stopped working rescently. I have worked out that it is because they now require .xls at the end of a filename where previoulsy they had not. I don't know what i have changed (nothing to my knowledge) but i am getting error messages without the Ext. My concern is that something has changed without my own obvious 'doing' that has caused the macros to stop working.
e.g.

Workbooks("CONSOLIDATION&quot.Worksheets("Sheet1&quot.Activate
now requires
Workbooks("CONSOLIDATION.xls&quot.Worksheets("Sheet1&quot.Activate
for it to work.

Does anybody know why??

 

[JustinEzequiel]

Windows Explorer settings

"Hide file extensions for known file types"

you had it 'off' but now it is 'on'

or for the "Excel files" file type, you have the "always show extension" checked

 

[Westicle]

Thanks, i was starting to lose my sanity wondering if it had worked before or not!!