trade station 9.0 platform

I took off almost a year from trading, I intend to come back to trading soon. I have window XP professional

anyone can tell me please if trade station 9.0 is compatible with window xp?
Yes it is compatible with Windows XP, you can read more about the system requirements here:

What you should be more concerned about is your hardware and if that matches the minimum requirements for the type of user that you are:

Minimum Requirements User
The common profile of the minimum requirements user is a TradeStation platform user who is not sensitive to real-time market data updates and makes decisions on market analysis that is not time sensitive. Traders that fit this profile are usually position traders or end-of-day traders.

Standard User
A standard user is generally anyone who is moderately sensitive to real-time market data updates and makes intraday decisions based on intraday market analysis. Traders that fit this profile are swing or trend traders. This type of user generally doesn’t need more than a handful of market data requests and follows specific symbols that are not extremely active. The standard user doesn’t rely on processor-intensive analysis techniques running real time on multiple charts.

Power User
A power user is generally a user utilizing computationally intensive EasyLanguage studies, utilizing large amounts of tick or intraday data (for example, several tick-based charts of highly active symbols such as Google, APPL or @ES, or several strategies with Look-Inside-Bar to the tick level enabled), or generating a large amount of trading activity. Traders that fit this profile are the active TradeStation traders or the user who requires following various active markets at the same time using complex EasyLanguage studies and strategy optimizations.