Receiving FLEXlm Error -88,309: System Clock Has Been Set Back

Receiving FLEXlm Error -88,309: System Clock Has Been Set Back


Receiving FLEXlm Error -88,309: System Clock Has Been Set Back


When attempting to checkout a license, the following FLEXlm Error is received: -88,309: System clock has been set back. How do can this be resolved?
Alternative terminology baddate, windback



NOTE: For security reasons, the following information is not to be shared with Enduser customers.

The way our method works is to examine file dates in certain directories, and if dates are found > 24 hours in the future, then to deny usage. This is to prevent system clock tampering to allow extended usage of licenses. You will need to change all the files with dates in the future back to the current date.

The directories which you need to check for these files are:

For Windows
(windows or winnt)
the directory where the app is located

v6+ checks these directories

It is recommended to write a batch file or binary to do this that looks like it does something else as providing this information to your end user could enable them to get round the licensing on your software.

The ls_a_check_baddate behavior is as mentioned below:
During the initial handshake between the license server and the client, the system of the client is compared with the system time of the server.
If it is a permanent license, no error is thrown on time differences or bad date checks.
If it is an expiring license, then:
- If bad date on the server is detected, then the error “LM_BADSYSDATE” (-88, minor error 335) is thrown
- If the difference between the client time and server time is more than 24 hrs, then “LM_CLOCKBAD” (-34, minor error 336) is thrown
- If both of the above errors are present, only the first one (LM_BADSYSDATE) is thrown.
A bad date is detected if one of the system files has a last modification time stamp that is greater than the current system time (adjusting for some tolerance)."
Another possibility would be a discrepancy in the time/date between the various machines involved ( server / client / mapped drive's machine).
Labels (1)
Was this article helpful? Yes No
No ratings
Version history
Revision #:
2 of 2
Last update:
‎Oct 05, 2020 04:23 AM
Updated by: