Windows keeps an 8.3 file name for every file to ensure compatility.
So if you have the files
test1.ext
test2.ext
test3.long
the last file gets stored with the alternative name
TEST3~1.LON
thus matching the pattern *1.*.
You can execute dir /x to see all 8.3 file names.
Fixes:
To strip all files in the directory directory of their 8.3 name, execute
fsutil 8dot3name strip directory
To strip all files in the directory directory of their 8.3 name, including those in subdirectories, execute
fsutil 8dot3name strip directory /s
To disable 8.3 file names on the drive drive: (only affects newly created files), execute
fsutil 8dot3name set drive: 1
To disable 8.3 file names altogether (only affects newly created files), execute
fsutil 8dot3name set 1
For the complete syntax, execute
fsutil 8dot3name strip & fsutil 8dot3name set
Furhter information: