Bypassing Variables and errors in CMD

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452KB, 641x478px

Trying to copy a file with a batch im writing.
Everything worked up until now, where i put

xcopy tempFile.txt "%date%-%time%.txt"

It specifies it as a file, but i always get
Invalid path
0 File(s) copied
Why wont windows let me assign a variable from the console (ie %time% and %date%) to a filename?
If i change the output to
xcopy tempFile.txt "SomeBlandFileName.txt"

it works fine, but thats not what i want.

Any help /g/?
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