Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

We are using robocopy with MIR switch to backup our Microsoft Access Databases, i.e., .accdb, and .mdb files. Interesting thing with Access database files is that you can open a database, add a few records into a table, close the db and the size of the database file will not change. Will robocopy know that he has to copy this file next time when he does the backup?


share|improve this question
up vote 1 down vote accepted

Changing the file not necessarily leads to a change in the file's size, but typically (i.e. unless a sufficiently privileged process has changed that) the following always happens:

  • the "last modified" timestamp of the file is updated to the current timestamp
  • the "archive" bit is touched (if it was not set, it is set by the OS automatically)

Robocopy would compare the "last modified" timestamp of the destination with that of the source and copy when these two differ (this behavior might be tweaked according to your requirements using the /xn and /xo switches). Robocopy would only honor (and reset) the archive file attribute when you use /m switch - see the robocopy documentation for details.

share|improve this answer
Great answer, tnx a lot. – I don't know. Jan 21 '13 at 10:13

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.