Error or Exception when installing license key

You may encounter the following error when attempting to enter a license key:

java.lang.NumberFormatException: For input string

This error indicates a problem with the format of the license.dat file and is usually caused by a missing line feed after a \\ character. In the example below, the second and third lines of the license key have been merged.

FEATURE systems uptime 7.0 permanent uncounted HOSTID=00096ba550be \\
NOTICE="UD00477 5738-01" SN=23 TS_OK SIGN="02DA 1623 64E5 62E2 \\ 21FE DD79 B2A5 B93A 1554 E6C3 0601 0C9B FB82 BA08 837B D156 \\
9D73 C6CA 1210 5ADD C9E8"

To resolve the problem, reformat the license (as shown below) by inserting a line break after each \\ character.

FEATURE systems uptime 7.0 permanent uncounted HOSTID=00096ba550be \\
NOTICE="UD00477 5738-01" SN=23 TS_OK SIGN="02DA 1623 64E5 62E2 \\
21FE DD79 B2A5 B93A 1554 E6C3 0601 0C9B FB82 BA08 837B D156 \\
9D73 C6CA 1210 5ADD C9E8"